Associate Professor (tenure track) Takashi Nishikata and colleagues have developed new synthetic protocol for cis- and trans- alkenes.

Hydroalkylation of alkynes is an indispensable reaction to synthesize alkylated alkenes. There are many reports on hydroarylation reactions, although stereoselective hydroalkylation reactions have not been well-studied yet. Especially, the addition of functionalized tertiary-alkyl groups is difficult owing to their steric hindrance. Therefore, controlling trans- and cis-hydroalkylations is challenging.

Associate Professor (tenure track) Takashi Nishikata and colleagues at the Graduate School of Sciences and Technology for Innovation (Department of Applied Chemistry) found that the reaction of α-bromocarbonyl compounds and alkynes in the presence of a copper catalyst undergoes controlled trans- and cis-hydroalkylations. When hydrosilane was used as a hydrogen source, very congested cis-tert-alkylated alkenes (i.e., trans-hydroalkylation) were obtained. On the other hand, alcohol as a hydrogen source yielded trans-tert-alkylated alkenes (i.e., cis-hydroalkylation).

The results were published in ACS Catalysis (IF=9.3), and ranked within the magazine's top 20 for number of times accessed.

 

 

 

Tandem Reactions Enable Trans- and Cis-Hydro-Tertiary-Alkylations Catalyzed by a Copper Salt

Kimiaki Nakamura, Takashi Nishikata*,

ACS Catalysis, 2017, 7, 1049–1052, DOI:  10.1021/acscatal.6b03343