トップ    差分バックアップリロードPages that link to here   一覧単語検索最終更新
   最終更新のRSS

In the course of our study on the synthetic application of cyanoboranes, we found interesting reactivity of bis(dialkylamino)cyanoboranes toward carbonyl compounds. In 1:1 reaction of the cyanoboranes with aldehydes at room temperature, α-dialkylamino nitriles were obtained in high yields [Ref. 1].

aminocyanation80.jpg

We designed aminoboranes bearing bulky diisopropyl groups on the boron atom. The aminoboranes served as a universal iminium ion generator, allowing use of free sec-amines in the Mannich-type reaction as the source of the amino group through facile amino group exchange on the boron atom [Ref. 2].

Mannich-type reaction80.jpg

The reaction protocol could be extended to other amination reactions, such as reductive amination [Ref. 3] and Ugi reactions [Ref. 4].

reductive amination80.jpg
 
Ugi reaction80.jpg

More recently, we found that diphenylborinic acid derivatives serve as “catalytic” iminium ion generators in the Mannich-type reactions [Ref. 5].

catalytic iminium ion generator80.jpg
 

References

トップ    差分バックアップリロードPages that link to here   一覧単語検索最終更新
   最終更新のRSS
Last-modified: 2009-01-21 (水) 18:12:33 (4700d)