2024 State of Marketing Report – by HubspotMarius Sescu
https://www.hubspot.com/state-of-marketing
· Scaling relationships and proving ROI
· Social media is the place for search, sales, and service
· Authentic influencer partnerships fuel brand growth
· The strongest connections happen via call, click, chat, and camera.
· Time saved with AI leads to more creative work
· Seeking: A single source of truth
· TLDR; Get on social, try AI, and align your systems.
· More human marketing, powered by robots
ChatGPT is a revolutionary addition to the world since its introduction in 2022. A big shift in the sector of information gathering and processing happened because of this chatbot. What is the story of ChatGPT? How is the bot responding to prompts and generating contents? Swipe through these slides prepared by Expeed Software, a web development company regarding the development and technical intricacies of ChatGPT!
Product Design Trends in 2024 | Teenage EngineeringsPixeldarts
The realm of product design is a constantly changing environment where technology and style intersect. Every year introduces fresh challenges and exciting trends that mold the future of this captivating art form. In this piece, we delve into the significant trends set to influence the look and functionality of product design in the year 2024.
How Race, Age and Gender Shape Attitudes Towards Mental HealthThinkNow
Mental health has been in the news quite a bit lately. Dozens of U.S. states are currently suing Meta for contributing to the youth mental health crisis by inserting addictive features into their products, while the U.S. Surgeon General is touring the nation to bring awareness to the growing epidemic of loneliness and isolation. The country has endured periods of low national morale, such as in the 1970s when high inflation and the energy crisis worsened public sentiment following the Vietnam War. The current mood, however, feels different. Gallup recently reported that national mental health is at an all-time low, with few bright spots to lift spirits.
To better understand how Americans are feeling and their attitudes towards mental health in general, ThinkNow conducted a nationally representative quantitative survey of 1,500 respondents and found some interesting differences among ethnic, age and gender groups.
Technology
For example, 52% agree that technology and social media have a negative impact on mental health, but when broken out by race, 61% of Whites felt technology had a negative effect, and only 48% of Hispanics thought it did.
While technology has helped us keep in touch with friends and family in faraway places, it appears to have degraded our ability to connect in person. Staying connected online is a double-edged sword since the same news feed that brings us pictures of the grandkids and fluffy kittens also feeds us news about the wars in Israel and Ukraine, the dysfunction in Washington, the latest mass shooting and the climate crisis.
Hispanics may have a built-in defense against the isolation technology breeds, owing to their large, multigenerational households, strong social support systems, and tendency to use social media to stay connected with relatives abroad.
Age and Gender
When asked how individuals rate their mental health, men rate it higher than women by 11 percentage points, and Baby Boomers rank it highest at 83%, saying it’s good or excellent vs. 57% of Gen Z saying the same.
Gen Z spends the most amount of time on social media, so the notion that social media negatively affects mental health appears to be correlated. Unfortunately, Gen Z is also the generation that’s least comfortable discussing mental health concerns with healthcare professionals. Only 40% of them state they’re comfortable discussing their issues with a professional compared to 60% of Millennials and 65% of Boomers.
Race Affects Attitudes
As seen in previous research conducted by ThinkNow, Asian Americans lag other groups when it comes to awareness of mental health issues. Twenty-four percent of Asian Americans believe that having a mental health issue is a sign of weakness compared to the 16% average for all groups. Asians are also considerably less likely to be aware of mental health services in their communities (42% vs. 55%) and most likely to seek out information on social media (51% vs. 35%).
AI Trends in Creative Operations 2024 by Artwork Flow.pdfmarketingartwork
This article is all about what AI trends will emerge in the field of creative operations in 2024. All the marketers and brand builders should be aware of these trends for their further use and save themselves some time!
A report by thenetworkone and Kurio.
The contributing experts and agencies are (in an alphabetical order): Sylwia Rytel, Social Media Supervisor, 180heartbeats + JUNG v MATT (PL), Sharlene Jenner, Vice President - Director of Engagement Strategy, Abelson Taylor (USA), Alex Casanovas, Digital Director, Atrevia (ES), Dora Beilin, Senior Social Strategist, Barrett Hoffher (USA), Min Seo, Campaign Director, Brand New Agency (KR), Deshé M. Gully, Associate Strategist, Day One Agency (USA), Francesca Trevisan, Strategist, Different (IT), Trevor Crossman, CX and Digital Transformation Director; Olivia Hussey, Strategic Planner; Simi Srinarula, Social Media Manager, The Hallway (AUS), James Hebbert, Managing Director, Hylink (CN / UK), Mundy Álvarez, Planning Director; Pedro Rojas, Social Media Manager; Pancho González, CCO, Inbrax (CH), Oana Oprea, Head of Digital Planning, Jam Session Agency (RO), Amy Bottrill, Social Account Director, Launch (UK), Gaby Arriaga, Founder, Leonardo1452 (MX), Shantesh S Row, Creative Director, Liwa (UAE), Rajesh Mehta, Chief Strategy Officer; Dhruv Gaur, Digital Planning Lead; Leonie Mergulhao, Account Supervisor - Social Media & PR, Medulla (IN), Aurelija Plioplytė, Head of Digital & Social, Not Perfect (LI), Daiana Khaidargaliyeva, Account Manager, Osaka Labs (UK / USA), Stefanie Söhnchen, Vice President Digital, PIABO Communications (DE), Elisabeth Winiartati, Managing Consultant, Head of Global Integrated Communications; Lydia Aprina, Account Manager, Integrated Marketing and Communications; Nita Prabowo, Account Manager, Integrated Marketing and Communications; Okhi, Web Developer, PNTR Group (ID), Kei Obusan, Insights Director; Daffi Ranandi, Insights Manager, Radarr (SG), Gautam Reghunath, Co-founder & CEO, Talented (IN), Donagh Humphreys, Head of Social and Digital Innovation, THINKHOUSE (IRE), Sarah Yim, Strategy Director, Zulu Alpha Kilo (CA).
Trends In Paid Search: Navigating The Digital Landscape In 2024Search Engine Journal
The search marketing landscape is evolving rapidly with new technologies, and professionals, like you, rely on innovative paid search strategies to meet changing demands.
It’s important that you’re ready to implement new strategies in 2024.
Check this out and learn the top trends in paid search advertising that are expected to gain traction, so you can drive higher ROI more efficiently in 2024.
You’ll learn:
- The latest trends in AI and automation, and what this means for an evolving paid search ecosystem.
- New developments in privacy and data regulation.
- Emerging ad formats that are expected to make an impact next year.
Watch Sreekant Lanka from iQuanti and Irina Klein from OneMain Financial as they dive into the future of paid search and explore the trends, strategies, and technologies that will shape the search marketing landscape.
If you’re looking to assess your paid search strategy and design an industry-aligned plan for 2024, then this webinar is for you.
5 Public speaking tips from TED - Visualized summarySpeakerHub
From their humble beginnings in 1984, TED has grown into the world’s most powerful amplifier for speakers and thought-leaders to share their ideas. They have over 2,400 filmed talks (not including the 30,000+ TEDx videos) freely available online, and have hosted over 17,500 events around the world.
With over one billion views in a year, it’s no wonder that so many speakers are looking to TED for ideas on how to share their message more effectively.
The article “5 Public-Speaking Tips TED Gives Its Speakers”, by Carmine Gallo for Forbes, gives speakers five practical ways to connect with their audience, and effectively share their ideas on stage.
Whether you are gearing up to get on a TED stage yourself, or just want to master the skills that so many of their speakers possess, these tips and quotes from Chris Anderson, the TED Talks Curator, will encourage you to make the most impactful impression on your audience.
See the full article and more summaries like this on SpeakerHub here: https://speakerhub.com/blog/5-presentation-tips-ted-gives-its-speakers
See the original article on Forbes here:
http://www.forbes.com/forbes/welcome/?toURL=http://www.forbes.com/sites/carminegallo/2016/05/06/5-public-speaking-tips-ted-gives-its-speakers/&refURL=&referrer=#5c07a8221d9b
ChatGPT and the Future of Work - Clark Boyd Clark Boyd
Everyone is in agreement that ChatGPT (and other generative AI tools) will shape the future of work. Yet there is little consensus on exactly how, when, and to what extent this technology will change our world.
Businesses that extract maximum value from ChatGPT will use it as a collaborative tool for everything from brainstorming to technical maintenance.
For individuals, now is the time to pinpoint the skills the future professional will need to thrive in the AI age.
Check out this presentation to understand what ChatGPT is, how it will shape the future of work, and how you can prepare to take advantage.
A brief introduction to DataScience with explaining of the concepts, algorithms, machine learning, supervised and unsupervised learning, clustering, statistics, data preprocessing, real-world applications etc.
It's part of a Data Science Corner Campaign where I will be discussing the fundamentals of DataScience, AIML, Statistics etc.
Time Management & Productivity - Best PracticesVit Horky
Here's my presentation on by proven best practices how to manage your work time effectively and how to improve your productivity. It includes practical tips and how to use tools such as Slack, Google Apps, Hubspot, Google Calendar, Gmail and others.
The six step guide to practical project managementMindGenius
The six step guide to practical project management
If you think managing projects is too difficult, think again.
We’ve stripped back project management processes to the
basics – to make it quicker and easier, without sacrificing
the vital ingredients for success.
“If you’re looking for some real-world guidance, then The Six Step Guide to Practical Project Management will help.”
Dr Andrew Makar, Tactical Project Management
2024 State of Marketing Report – by HubspotMarius Sescu
https://www.hubspot.com/state-of-marketing
· Scaling relationships and proving ROI
· Social media is the place for search, sales, and service
· Authentic influencer partnerships fuel brand growth
· The strongest connections happen via call, click, chat, and camera.
· Time saved with AI leads to more creative work
· Seeking: A single source of truth
· TLDR; Get on social, try AI, and align your systems.
· More human marketing, powered by robots
ChatGPT is a revolutionary addition to the world since its introduction in 2022. A big shift in the sector of information gathering and processing happened because of this chatbot. What is the story of ChatGPT? How is the bot responding to prompts and generating contents? Swipe through these slides prepared by Expeed Software, a web development company regarding the development and technical intricacies of ChatGPT!
Product Design Trends in 2024 | Teenage EngineeringsPixeldarts
The realm of product design is a constantly changing environment where technology and style intersect. Every year introduces fresh challenges and exciting trends that mold the future of this captivating art form. In this piece, we delve into the significant trends set to influence the look and functionality of product design in the year 2024.
How Race, Age and Gender Shape Attitudes Towards Mental HealthThinkNow
Mental health has been in the news quite a bit lately. Dozens of U.S. states are currently suing Meta for contributing to the youth mental health crisis by inserting addictive features into their products, while the U.S. Surgeon General is touring the nation to bring awareness to the growing epidemic of loneliness and isolation. The country has endured periods of low national morale, such as in the 1970s when high inflation and the energy crisis worsened public sentiment following the Vietnam War. The current mood, however, feels different. Gallup recently reported that national mental health is at an all-time low, with few bright spots to lift spirits.
To better understand how Americans are feeling and their attitudes towards mental health in general, ThinkNow conducted a nationally representative quantitative survey of 1,500 respondents and found some interesting differences among ethnic, age and gender groups.
Technology
For example, 52% agree that technology and social media have a negative impact on mental health, but when broken out by race, 61% of Whites felt technology had a negative effect, and only 48% of Hispanics thought it did.
While technology has helped us keep in touch with friends and family in faraway places, it appears to have degraded our ability to connect in person. Staying connected online is a double-edged sword since the same news feed that brings us pictures of the grandkids and fluffy kittens also feeds us news about the wars in Israel and Ukraine, the dysfunction in Washington, the latest mass shooting and the climate crisis.
Hispanics may have a built-in defense against the isolation technology breeds, owing to their large, multigenerational households, strong social support systems, and tendency to use social media to stay connected with relatives abroad.
Age and Gender
When asked how individuals rate their mental health, men rate it higher than women by 11 percentage points, and Baby Boomers rank it highest at 83%, saying it’s good or excellent vs. 57% of Gen Z saying the same.
Gen Z spends the most amount of time on social media, so the notion that social media negatively affects mental health appears to be correlated. Unfortunately, Gen Z is also the generation that’s least comfortable discussing mental health concerns with healthcare professionals. Only 40% of them state they’re comfortable discussing their issues with a professional compared to 60% of Millennials and 65% of Boomers.
Race Affects Attitudes
As seen in previous research conducted by ThinkNow, Asian Americans lag other groups when it comes to awareness of mental health issues. Twenty-four percent of Asian Americans believe that having a mental health issue is a sign of weakness compared to the 16% average for all groups. Asians are also considerably less likely to be aware of mental health services in their communities (42% vs. 55%) and most likely to seek out information on social media (51% vs. 35%).
AI Trends in Creative Operations 2024 by Artwork Flow.pdfmarketingartwork
This article is all about what AI trends will emerge in the field of creative operations in 2024. All the marketers and brand builders should be aware of these trends for their further use and save themselves some time!
A report by thenetworkone and Kurio.
The contributing experts and agencies are (in an alphabetical order): Sylwia Rytel, Social Media Supervisor, 180heartbeats + JUNG v MATT (PL), Sharlene Jenner, Vice President - Director of Engagement Strategy, Abelson Taylor (USA), Alex Casanovas, Digital Director, Atrevia (ES), Dora Beilin, Senior Social Strategist, Barrett Hoffher (USA), Min Seo, Campaign Director, Brand New Agency (KR), Deshé M. Gully, Associate Strategist, Day One Agency (USA), Francesca Trevisan, Strategist, Different (IT), Trevor Crossman, CX and Digital Transformation Director; Olivia Hussey, Strategic Planner; Simi Srinarula, Social Media Manager, The Hallway (AUS), James Hebbert, Managing Director, Hylink (CN / UK), Mundy Álvarez, Planning Director; Pedro Rojas, Social Media Manager; Pancho González, CCO, Inbrax (CH), Oana Oprea, Head of Digital Planning, Jam Session Agency (RO), Amy Bottrill, Social Account Director, Launch (UK), Gaby Arriaga, Founder, Leonardo1452 (MX), Shantesh S Row, Creative Director, Liwa (UAE), Rajesh Mehta, Chief Strategy Officer; Dhruv Gaur, Digital Planning Lead; Leonie Mergulhao, Account Supervisor - Social Media & PR, Medulla (IN), Aurelija Plioplytė, Head of Digital & Social, Not Perfect (LI), Daiana Khaidargaliyeva, Account Manager, Osaka Labs (UK / USA), Stefanie Söhnchen, Vice President Digital, PIABO Communications (DE), Elisabeth Winiartati, Managing Consultant, Head of Global Integrated Communications; Lydia Aprina, Account Manager, Integrated Marketing and Communications; Nita Prabowo, Account Manager, Integrated Marketing and Communications; Okhi, Web Developer, PNTR Group (ID), Kei Obusan, Insights Director; Daffi Ranandi, Insights Manager, Radarr (SG), Gautam Reghunath, Co-founder & CEO, Talented (IN), Donagh Humphreys, Head of Social and Digital Innovation, THINKHOUSE (IRE), Sarah Yim, Strategy Director, Zulu Alpha Kilo (CA).
Trends In Paid Search: Navigating The Digital Landscape In 2024Search Engine Journal
The search marketing landscape is evolving rapidly with new technologies, and professionals, like you, rely on innovative paid search strategies to meet changing demands.
It’s important that you’re ready to implement new strategies in 2024.
Check this out and learn the top trends in paid search advertising that are expected to gain traction, so you can drive higher ROI more efficiently in 2024.
You’ll learn:
- The latest trends in AI and automation, and what this means for an evolving paid search ecosystem.
- New developments in privacy and data regulation.
- Emerging ad formats that are expected to make an impact next year.
Watch Sreekant Lanka from iQuanti and Irina Klein from OneMain Financial as they dive into the future of paid search and explore the trends, strategies, and technologies that will shape the search marketing landscape.
If you’re looking to assess your paid search strategy and design an industry-aligned plan for 2024, then this webinar is for you.
5 Public speaking tips from TED - Visualized summarySpeakerHub
From their humble beginnings in 1984, TED has grown into the world’s most powerful amplifier for speakers and thought-leaders to share their ideas. They have over 2,400 filmed talks (not including the 30,000+ TEDx videos) freely available online, and have hosted over 17,500 events around the world.
With over one billion views in a year, it’s no wonder that so many speakers are looking to TED for ideas on how to share their message more effectively.
The article “5 Public-Speaking Tips TED Gives Its Speakers”, by Carmine Gallo for Forbes, gives speakers five practical ways to connect with their audience, and effectively share their ideas on stage.
Whether you are gearing up to get on a TED stage yourself, or just want to master the skills that so many of their speakers possess, these tips and quotes from Chris Anderson, the TED Talks Curator, will encourage you to make the most impactful impression on your audience.
See the full article and more summaries like this on SpeakerHub here: https://speakerhub.com/blog/5-presentation-tips-ted-gives-its-speakers
See the original article on Forbes here:
http://www.forbes.com/forbes/welcome/?toURL=http://www.forbes.com/sites/carminegallo/2016/05/06/5-public-speaking-tips-ted-gives-its-speakers/&refURL=&referrer=#5c07a8221d9b
ChatGPT and the Future of Work - Clark Boyd Clark Boyd
Everyone is in agreement that ChatGPT (and other generative AI tools) will shape the future of work. Yet there is little consensus on exactly how, when, and to what extent this technology will change our world.
Businesses that extract maximum value from ChatGPT will use it as a collaborative tool for everything from brainstorming to technical maintenance.
For individuals, now is the time to pinpoint the skills the future professional will need to thrive in the AI age.
Check out this presentation to understand what ChatGPT is, how it will shape the future of work, and how you can prepare to take advantage.
A brief introduction to DataScience with explaining of the concepts, algorithms, machine learning, supervised and unsupervised learning, clustering, statistics, data preprocessing, real-world applications etc.
It's part of a Data Science Corner Campaign where I will be discussing the fundamentals of DataScience, AIML, Statistics etc.
Time Management & Productivity - Best PracticesVit Horky
Here's my presentation on by proven best practices how to manage your work time effectively and how to improve your productivity. It includes practical tips and how to use tools such as Slack, Google Apps, Hubspot, Google Calendar, Gmail and others.
The six step guide to practical project managementMindGenius
The six step guide to practical project management
If you think managing projects is too difficult, think again.
We’ve stripped back project management processes to the
basics – to make it quicker and easier, without sacrificing
the vital ingredients for success.
“If you’re looking for some real-world guidance, then The Six Step Guide to Practical Project Management will help.”
Dr Andrew Makar, Tactical Project Management
Beginners Guide to TikTok for Search - Rachel Pearson - We are Tilt __ Bright...
Le diiodure de samarium
1. Nicolaou, K. C.; Ellery, S. P.; Chen, J. S. Angew. Chem. Int. Ed. 2009, 48, 7140.
1
2. Introduction
Les Lanthanides
Orbitales 4f : OA contractées, faible recouvrement/ligands
Ln très électropositifs→ complexes formés à fort caractère ionique→
acides de Lewis « durs » ↔ affinité ligands « durs » (O, N)
Ln(III) est l’état d’oxydation le plus stable: Ln(II) potentiellt réducteur
Couleur Ln(II) intense et dépendante des ligands (transition 4f → 5d)
Kagan, H. B. Lanthanides: Chemistry and Use in Organic Synthesis 1998, Vol. 2, 155, Springer.
2
3. Introduction SmI2
Découvert et développé par Henri
Kagan à la fin des années 70
Popularisé par Gary Molander dans les
années 90
Aujourd’hui très utilisé en synthèse
totale, notamment pour la formation de
liaisons C-C
Kagan, H. B.; Namy, J. L.; Girard, P. J. Am. Chem. Soc. 1980, 102, 2693. Kagan, H. B. Lanthanides: Chemistry and Use in Organic
Synthesis 1998, Vol. 2, 155, Springer. Molander, G. Chem. Rev. 1992, 92, 29. Molander, G.; Harris, C. R. Chem. Rev. 1996, 96, 307. 3
Molander, G.; Harris, C. R. Tetrahedron 1998, 54, 3321. Kagan, H. B. Tetrahedron 2003, 59, 10351.
4. Introduction SmI2
Préparation: Achat:
I2, THF, 24h
CH2I2 ou
ICH2CH2I
Sm SmI2
THF, TA, 1h 0,1 M dans le THF 25 mL: 25 €
bleu profond
O2!
Qualité?
CHI3, THF, ))), TA Conservation?
SmI3
(solution jaune)
Molander, G. Org. React. 1994, 46, 211.
4
5. Propriétés et Réactivité SmI2
Fort potentiel réducteur du Sm(II) :-1,55V dans H2O
(jusqu’à -2,05V en présence de HMPA)
Très sensible à l’oxygène (Sm(III) plus stable)
Compatible avec un milieu protique (H2O, MeOH,
t-BuOH)
5
6. Propriétés et Réactivité SmI2
Via transfert mono électronique
Activation des halogénures d’alkyle:
Sm(II) I2
RX R RSmI2
-Sm(III) I2X
réactivité réactivité ionique Méca radicalaire→
radicalaire "type magnésien"
intramoléculaire
Activation des carbonyles:
Sm(III)I2 Sm(III)I2
O (II) O Sm (II)
I2 O
Sm I2
R1 R2 R1 R2 R1 R2
réactivité radicalaire réactivité ionique
"type couplage pinacolique"
6
7. Propriétés et Réactivité SmI2
Le THF est le solvant de choix (plus rarement THP, PivCN, PhH):
synthèse SmI2 et bonne conservation
Généralement présence d’un donneur de protons (H2O, MeOH…)
Additif: HMPA (5-10%, cplxe violet, ↑réactivité), voire DMPU, H2O…
Bon acide de Lewis et très oxophile (Sm(III) et (II))
Grande chimio, et stéréosélectivité possible
7
8. Applications en synthèse SmI2
Réactions de Barbier
Réaction type Réformatsky
Réaction carbonyl-alcène
Réactions de fragmentation/d’élimination
8
9. Réactions de Barbier SmI2
O
OH
idéal en intramoléculaire
R2 R3
R1X
2eq. SmI2
R1SmI2
cétones fortmt énolisables
R1 R3
R2 compatibles
Approche de la synthèse du Phorbol (Carroll & Little)
H
SmI2, H
NiI2 cat., THF
O O H Catalyseurs les
OH 82-88% O
O
O OH plus courants de
I HO
SmI2:
OH
OH
Me Fe(III), NiI2, LiCl,
H Me
Me Me
H
OH H
O HO Cu(I)*, Co(II), Pd(0)
OH
Phorbol (diterpene)
Carroll, G. L.; Little, R. D. Org. Lett. 2000, 2, 2873.
*possibilité de transmétallation suivie d’addition conjuguée ou couplage Csp3-Csp3 9
10. Réactions de Barbier SmI2
Approche de la synthèse du Vinigrol (Matsuda)
OH Co-solvants les
Cl OBn OBn
plus courants de
SmI2,
HMPA, THF SmI2:
O 98%
OMOM OMOM HMPA, DMPU,
Me (15% sans HMPA) Me TMEDA, TMG, DBU,
Et3N, H2O…
SmI2/H2O/amine*
Me (↑ ↑ réactivité)
iPr
OH
OH
Me
OH
Vinigrol (diterpenoïde)
SmI2.HMPA4
Formation cycle à 8 (forme chaise) & diastéréosélectivité totale
Matsuda, F.; Miyashita, M.; Shirahama, H.; Sakai, T.; Kito, M. Synlett. 1997, 219.
* Dahlén, A.; Hilmersson, G. Eur. J. Inorg. Chem. 2004, 3393. 10
11. Réactions de Réformatsky SmI2
Formation d’un éther d’énol de samarium
(mécanisme radicalaire ou ionique selon X)
O
A SmI2 SmI2
O O O
X SmI2 R3 R4 R5
R1
R 1 R3 Aldol
R3 -SmI2X R1
R2 R 2
R2
SmI2
B
-SmI2X
SmI2 SmI2 X=I, Br, SO2R...
O O
SmI2
X X
R1 R1
R3 -SmI2X R3
R2 R2
Alternative au Zn:
Version intramoleculaire: ↑Rdts et ↑selectivités par chélation du Sm
Efficace sur des cétones encombrées (en tant qu’électrophile)
11
12. Réactions de Réformatsky SmI2
Approche de la synthèse du Taxol (Arseniyadis)
I
O Sm O
Me O Me O
O O
SmI2 (2 eq.), THF, 0°C O
O O
Me
Me O O
H H
OMe Me OMe Me
O O
Me Me
Me
O Sm(III)ene diolate
74%
AcO O
Me O O
HO Me O
Me 11
Ph O C HO 12
B O C
A B Me
D O A
O
BzHN O H H
HO OBz OAc 1
OMe Me
Taxus brevifolia OH O
Me
Taxol
Sélectivité par chélation du samarium (C12)
Arseniyadis, S.; Toupet, L.; Birlirakis, N.; Hamon, B. Eur. J. Org. Chem. 2005, 4082.
12
13. Réactions de Réformatsky SmI2
Synthèse du Taxol (Mukaiyama)
Bn BnO O
Br O Me Me OBn TBSO Me
O SmI2, THF, -78°C
Me Me r.d.: 5/1
70%
O O OPMB OH
Me
TBS PMBO OBn
Cycle B du Taxol
Forte chimiosélectivité et stéréosélectivité
Formation d’un cycle à 8 chaînons
Mukaiyama, T.; Shiina, I.; Iwadare, H.; Saitoh, M.; Nishimura, T.; Ohkawa, N.; Sakoh, H.; Nishimura, K.; Tani, Y.; Hasegawa,
M.; Yamada, K.; Saitoh, K. Chem. Eur. J. 1999, 5, 121. 13
14. Réactions carbonyl-alcène SmI2
R3 R5
SmI2 OH H
O O R4 R6
SmI2 R1 R5
1
R 2
R 1 2 R2 R6
R R R3 R4
Synthèse de la Patchoulénone (Banwell)
Me Me Me
SmI2, HMPA,
Me PhSH, THF
74%
O H Me OH Me
OBn OBn O
patchoulénone
(sesquiterpène)
PhSH donneur de H.
Banwell, M.; McLeod M. Chem. Commun. 1998, 1851.
Banwell, M; Hockless, D. C. R.; McLeod, M. D. New. J. Chem. 2003, 27, 50. 14
15. Réactions carbonyl-alcène SmI2
Synthèse totale de la Brevetoxine B (Nakata)
e + SmI2 SmI2
O Me
Me O
H SmI2 (5 eq.), Me
H Me H H OH
O MeOH (5eq.) O
CO2Et HO E
D
CO2Et
EtO2C O THF, 0°C C D O H
O H EtO2C
H O H
Me H H Me
pTsOH, PhMe,
80°C
Cycles jonction trans H
Me
Me H O
HO O E O
ET chaise, chélation EtO2C
O
C D
H
O H
H H
ester/cétyle Me
79% sur les deux étapes
Matsuo, G.; Kawamura, K.; Hori, N.; Matsukura, H.; Nakata, T. J. Am. Chem. Soc. 2004, 126, 14983.
Hori, N.; Matsukura, H.; Matsuho, G.; Nakata, T. Tetrahedron 2002, 58, 1853. 15
16. Réactions carbonyl-alcène SmI2
Synthèse totale de la Brevetoxine B (Nakata)
Me
Me H H O
HO O E O
C D
EtO2C O H
O H
H H Me
HO CHO
Me
K
H O O
J
H
H
Me Me HO I
Me H O O H
H Me H
O O E F G H H
A B C D O
O H H Me
O O O H
H H H Me SmI2:
Neurotoxine produite par des Dinoflagellates Brevetoxine B -carbonyl-alcène
(polyéther "marin") -Reformatsky
Matsuo, G.; Kawamura, K.; Hori, N.; Matsukura, H.; Nakata, T. J. Am. Chem. Soc. 2004, 126, 14983.
16
17. Réactions carbonyl-alcène SmI2
Approche de la synthèse de la Pleuromutiline (Procter)
AcO O
OAc
SmI2 (2,5 eq.)
THF/t-BuOH (5/1)
0°C, 86%
O HO H CO Me OH
2
CO2Me
OH
O
O
O H OH H
BzMO
O OTBS
O
Pleuromutiline
(antibactérien)
Helm.; M. D.; Da Silva, M.; Sucunza, D.; Findley, T. J. K.; Procter, D. Angew. Chem. Int. Ed. 2009, 48, 9315.
17
18. Réactions carbonyl-alcène SmI2
AcO O
OAc
SmI2 (2,5 eq.)
THF/t-BuOH (5/1)
O 0°C, 86% HO H CO Me OH
2
CO2Me
4 centres contrôlés
aldolisation
OAc O O
AcO AcO H
OMe OMe
5-exo-trig O O O
H OMe H SmIII
H SmIII
O
SmIII O O
O
chimiosélectivité
Chimio- et stéréosélectivité par chélation
Helm.; M. D.; Da Silva, M.; Sucunza, D.; Findley, T. J. K.; Procter, D. Angew. Chem. Int. Ed. 2009, 48, 9315.
18
19. Réactions carbonyl-alcène SmI2
Synthèse de l’acide Martinellique (Naito)
O
NOBn
CO2Et HN
MeO2C
MeO2C
SmI2 (5eq.)
N
t-BuOH/ THF (1,3/1) N
0°C
O
O
RACE: Radical Addition Cyclisation
Elimination
HN Me
HN
N Me
HO2C
H H
N N Me
N
H
NH Me
Martinella iquitosensis Acide Martinellique
(inhibiteur bradykinique)
Shirai, A.; Miyata, O.; Tohnai, M.; Miyata, M.; Procter, D. J.; Sucunza, D.; Naito, N. J. Org. Chem. 2008, 73, 4464.
19
20. Réactions carbonyl-alcène SmI2
Synthèse de l’acide Martinellique (Naito)
NOBn EtO O SmI
CO2Et 2
MeO2C BnO N
SmI2 (5eq.) H
MeO2C
N t-BuOH/ THF (1,3/1) H
0°C N
O O
O
BnO SmI2
HN N
MeO2C MeO2C CO2Et
41%
N N
O O
t-BuOH protonne les anions intermédiaires
29% Rdt avec n-Bu3SnH/AIBN
Shirai, A.; Miyata, O.; Tohnai, M.; Miyata, M.; Procter, D. J.; Sucunza, D.; Naito, N. J. Org. Chem. 2008, 73, 4464.
20
21. Réactions carbonyl-alcène SmI2
Synthèse de la Hyacinthacine A2 (Py)
CO2Et CO2Et CO2Et
O OH
BnO 3eq. SmI2, THF, BnO BnO H
N N +3eq. SmI2, THF N
8eq. H2O, -78°C
-78->25°C
64%, r.d. 9/1
BnO OBn BnO OBn BnO OBn
+ K2CO3,
EtOH
BnO O
HO
N
N BnO
Hyacinthacine A2 HO
(inhibiteur enzymatique) BnO H
HO H
59%
Réaction d’Umpolung
Muscari armeniacum
Desvergnes, S.; Py, S.; Vallée, Y. J. Org. Chem. 2005, 70, 1462.
Masson, G.; Cividino, P.; Py, S.; Vallée, Y. Angew. Chem. Int. Ed. 2003, 42, 2265. 21
22. Réactions carbonyl-alcène SmI2
Synthèse de l’Hypnophiline (Curran)
H H
SmI2
Me Me
O O
SmI2 (1,7 eq.)
Me O O
Me
Me O THF/HMPA (20/1), 0°C Me O
5-exo-trig
H
I2SmO I2SmO
Me H Me O Me H Me
Me O 5-exo-dig Me O
H H H O
HMPA indispenable pour un bon rdt (DMPU moins
diastéréosélective)
Fevig, T. L.; Elliott, R. L.; Curran, D. P. J. Am. Chem. Soc. 1988, 110, 5064.
22
23. Réactions carbonyl-alcène SmI2
Synthèse de l’Hypnophiline (Curran)
I2SmO OH OH
Me H Me O H Me O Me H Me
.
[H ] THF Me pTsOH O
Me O Me O acetone Me
H H H H 58% H H
OH
Me H Me
O
Hypnophiline
(sesquiterpene a activité Me
antibiotique) H O
Fevig, T. L.; Elliott, R. L.; Curran, D. P. J. Am. Chem. Soc. 1988, 110, 5064.
23
24. Réactions de fragmentation/d’élimination
fragmentation
O I2Sm I2Sm O
O O
n SmI2 n
n
R4 R4
n
1 4 4 1
R 1 R R1 R R
R
R2 R3 2 R3 R2 R3 R2 R3
R
n=3,4
Ouverture de cyclopropanes/butanes
élimination
O SmI2 O
O
X 2SmI2 H
R1 1 R3 R1 ↑rdts, rapide,
3
-SmI2X R 3
2R 2R
R R2 R gde tolérance fonctelle
X=Cl, Br, I, SO2R, NR2, OAc, OTMS, OTs, OH...
Coupure réductrice de carbonyle a-hétérosubstitué
24
25. Réactions de fragmentation SmI2
Approche de la synthèse du Cyclocitrinol (Schmalz)
Me O Me O Me O
H SmI2 (2,2 eq.) H H
H2O
H H H 43% H H
THF, TA
O
O I2SmO O
OSmI2 O
Synthèse d’un système bicyclo[4.4.1]undecane Me OH OH
Me Me
H
H H
HO O
Cyclocitrinol
(stérol issu d'un champignon
d'éponge marine)
Axinella sp.
Sheikh, S. E.; zu Greffen, A. M.; Lex, J.; Neudörfl, J.-L., Schmalz. H.-G. Synlett 2007, 1881.
25
26. Réactions de fragmentation SmI2
Synthèses des Guanacastépènes A et E (Sorensen & Shipe)
O PMP O PMP
O O
O [2+2] O
h, Et2O
Me Me 82% Me Me
Me Me
Me Me
i) SmI2 (2.5 eq.), HMPA (10eq.), THF
50%
ii) PhSeBr
Photocycloaddition [2+2] O
OPMP
O O
SePh
Fragmentation stéréocontrôlée Me Me Me
du cyclobutyle Me
Shipe, W. D.; Sorensen, E. J. J. Am. Chem. Soc. 2006, 128, 7025.
26
27. Réactions de fragmentation SmI2
Synthèses des Guanacastépènes A et E (Sorensen & Shipe)
O
O OH
H
OPMP AcO
O
O O
SePh Me
Me Me
Me
Me Guanacastépène A
Me Me
Me diterpènes
(activité antibiotique)
O O OH
H
AcO
Me Me Me
Me
Parc National de Guanacaste Guanacastépène E
(Costa Rica)
Shipe, W. D.; Sorensen, E. J. J. Am. Chem. Soc. 2006, 128, 7025.
Brady, S. F.; Singh, M. P.; Janso, J. E.; Clardy, J. J. Am. Chem. Soc. 2000, 122, 2116. 27
Brady, S. F.; Bondi, S. M. ; Clardy, J. J. Am. Chem. Soc. 2001, 123, 9900.
28. Réactions d’élimination SmI2
Synthèse de Bakkanes (Deprés)
Me Me O Me
Me Me Me
SmI2, TBAF, O
THF/H2O CH3COCl
O O
TA, 1h, 92% THF, 48h, 60-70%
H
O O O HO H OAc
9-acetoxyfukinanolide
Réduction sélective de la cétone/spirolactone
Me Me
Me Me
SmI2,
THF/H2O
O O
TA, 30min, 83%
O O O O HO H
OH
Double réduction de la cétone (reformée in situ par protonation de
l’énolate de samarium)
Hamelin, O.; Deprés, J.-P.; Greene, A. E.; Tinant, B.; Declercq, J.-P. J. Am. Chem. Soc. 1996, 118, 9992.
Hamelin, O.; Wang, Y.; Deprés, J.-P.; Greene, A. E. Angew. Chem. Int. Ed. 2000, 39(23), 4314. 28
29. Réactions d’élimination SmI2
Synthèse de Bakkanes (Deprés) Me
O
Me
O
Me Bakkénolide C
Me Me
HO H O
O Me
O
O HO H
OH
O Me
Me
O
Bakkénolide B
Me
AcO H O
Me
O
O Me
Me
O
Me Bakkénolide H
Petasites Formosanus
O H O
Me Me
Petasites Japonicus O O
Me
Hamelin, O.; Wang, Y.; Deprés, J.-P.; Greene, A. E. Angew. Chem. Int. Ed. 2000, 39(23), 4314.
29
30. Réactions d’élimination SmI2
Approche de la Pillaromycinone (White)
O
O O
H O O
SmI2 (2eq.), FeCl3 (cat.) H O
O THF, TA, 15 min >84%
HO2C
O H OTBDMS H
OTBDMS
OH
H
Seule méthode efficace OH
Conditions douce: compatible OH OH O
OH
O
avec l’alcool silylé Pyllaromycinone
(anthracycline antibiotique)
White, J. D.; Nolen, E. G.; Miller, C. H. J. Org. Chem. 1986, 51 (7), 1150.
30
31. Réactions d’élimination SmI2
Réduction de systèmes carbonyles a-hydroxylés
H
O BnOCH2Cl, SmI2 OH O
OBn OH
THF, 25°C, 20h
H via ène-réaction H
92% H
Barbier
SmI2, t-BuOH,
87%
THF, 25°C, 12h
HO
H
Caractéristique H
unique de SmI2 H
HO
H
H
2-Desoxystemodinone
diterpène
White, J. D.; Somers, T. C. J. Am. Chem. Soc. 1987, 109, 4424.
31
32. Conclusion SmI2
Conditions réactionnelles douces
Alternative au système Bu3SnH/AIBN (toxique,
dérivés stanniques difficiles à éliminer)
SmI2 impliqué dans des réactions radicalaires/ioniques:
Application aux réactions en cascade
32
33. Conclusion SmI2
Après étude fine du substrat et des conditions (solvant,
cosolvant, additifs, temp.):
Hautes chimio/stéréosélectivité accessibles
Rendements élevés
Utilisation croissante en synthèse totale depuis 30 ans
33