Copper-Catalyzed Tandem Asymmetric Borylation of β-Chloroalkyl Aryl Ketones and Related Compounds
作者:Quanbin Jiang、Tenglong Guo、Zhengkun Yu
DOI:10.1002/cctc.201402823
日期:2015.2
The Cu‐catalyzed, one‐pot tandem (asymmetric) borylation of β‐chloroalkyl aryl ketones via the in situ generated acyclic enones with bis(pinacolato)diboron was achieved efficiently to reach up to 97 % yield and 99 % enantioselectivity for the formal sp3 CCl borylation products. The present methodology provides an efficient alternative route to (chiral) alkylboron compounds.
Metal free catalytic hydroboration of multiple bonds in methanol using N-heterocyclic carbenes under open atmosphere
作者:Kun Wen、Jinbo Chen、Feng Gao、Pinaki S. Bhadury、Erkang Fan、Zhihua Sun
DOI:10.1039/c3ob41499j
日期:——
An easy to operate method of catalytic hydroboration of unsaturated compounds has been developed with wide substrate scope. Reactions of various aldimines, ketimines, α,β-unsaturated carbonyl compounds, and alkynes were successfully executed with bis(pinacolato)diboron and N-heterocyclic carbenes in methanol without requiring a transition metal or inert atmosphere.
The cleavage and transformation of alkenyl C(sp2)–N bonds is a significant synthetic challenge. Herein we described an unprecedented nickel-catalyzed reductive borylation of enaminones to synthesize β-ketone boronic esters. Notably, B2pin2 played the dual role in this process, and water served as a hydrogen source, which was transferred to target products. The air-stable nickel catalyst was applied