scholarly journals Intermolecular Rhodium-Catalysed Hydroamination of Non-Activated Olefins: Effect of Olefin, Amine, Phosphine and Phosphonium Salt

ChemPlusChem ◽  
2012 ◽  
Vol 77 (6) ◽  
pp. 445-454 ◽  
Author(s):  
Mireia Rodriguez-Zubiri ◽  
Christine Baudequin ◽  
Aurélien Béthegnies ◽  
Jean-Jacques Brunet
1996 ◽  
Vol 61 (12) ◽  
pp. 1798-1804 ◽  
Author(s):  
Albert Demonceau ◽  
François Simal ◽  
Corine A. Lemoine ◽  
Alfred F. Noels ◽  
Igor T. Chizhevsky ◽  
...  

The title compound was found to be an efficient catalyst for the selective cyclopropanation of activated olefins by ethyl diazoacetate. The cyclopropane yields range from moderate to good (75 to 95%) for activated olefins such as styrene and styrene derivatives, but are rather low (20 to 30%) for non-activated olefins such as terminal and cyclic alkenes. In the intermolecular competition, styrene was 45 times more reactive than cyclooctene. In all cases, trans (exo) cyclopropane predominated over the cis (endo) isomer.


Synthesis ◽  
2020 ◽  
Author(s):  
Lili Shi ◽  
Junkai Fu ◽  
Shuangqiu Gao ◽  
Le Chang ◽  
Binglin Wang

AbstractThe Mizoroki–Heck reaction is considered as one of the most ingenious and widely used methods for constructing C–C bonds. This reaction mainly focuses on activated olefins (styrenes, acrylates, or vinyl ethers) and aryl/vinyl (pseudo) halides. In comparison, the studies on unactivated alkenes and alkyl electrophiles are far less due to the low reactivity, poor selectivity, as well as competitive β-H elimination. In the past years, a growing interest has thus been devoted and significant breakthroughs have been achieved in the employment of unactivated alkenes and alkyl electrophiles as the reaction components, and this type of coupling is called as Heck-type or Heck-like reaction, which distinguishes from the traditional Heck reaction. Herein, we give a brief summary on Heck-type reaction between unactivated alkenes and alkyl electrophlies, covering its initial work, recent advancements, and mechanistic discussions.1 Introduction2 Intramolecular Heck-Type Reaction of Unactivated Alkenes and Alkyl Electrophiles2.1 Cobalt-Catalyzed Intramolecular Heck-Type Reaction2.2 Palladium-Catalyzed Intramolecular Heck-Type Reaction2.3 Nickel-Catalyzed Intramolecular Heck-Type Reaction2.4 Photocatalysis and Multimetallic Protocol for Intramolecular Heck-Type Reaction3 Intermolecular Heck-Type Reaction of Unactivated Alkenes and Alkyl Electrophiles3.1 Electrophilic Trifluoromethylating Reagent as Reaction Partners3.2 Alkyl Electrophiles as Reaction Partners4 Oxidative Heck-Type Reaction of Unactivated Alkenes and Alkyl Radicals5 Conclusions and Outlook


Synlett ◽  
2019 ◽  
Vol 30 (03) ◽  
pp. 338-342
Author(s):  
Yuta Suganuma ◽  
Shun Saito ◽  
Yuichi Kobayashi

Wittig reactions using carboxy (CO2H) ylides derived from a carboxylic phosphonium salt and NaN(TMS)2 (NaHMDS) in a 1:1 ratio were applied to the synthesis of 8-HEPE and 10-HDoHE, which are metabolites of eicosapentaenoic acid and docosahexaenoic acid, respectively. The attempted Wittig reaction of 3-(TBS-oxy)pentadeca-4E,6Z,9Z,12Z-tetraenal with the carboxy ylide (2 equiv) derived from Br– Ph3P+(CH2)4CO2H and NaHMDS (1:1) competed with the elimination of the TBS-oxy group at C3 to give a mixture of the Wittig product and the elimination product in 45–50% and 30–40% yields, respectively. The elimination was suppressed completely by using three equiv of the carboxy ylides in THF/HMPA (7–8:1), and the subsequent desilylation gave 8-HEPE in (R)- and (S)-forms. Similarly, both enantiomers of 10-HDoHE were synthesized.


ChemSusChem ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1825-1833 ◽  
Author(s):  
Yuya Hu ◽  
Sandra Peglow ◽  
Lars Longwitz ◽  
Marcus Frank ◽  
Jan Dirk Epping ◽  
...  
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