Ye Xincui, Sun Xianwei, Huang Zhenggang, Yang Na, Su Zhishan, Hu Changwei, Song Zhenlei
Key laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry, West China School of Pharmacy, Sichuan University, Chengdu, 610041, China.
Org Biomol Chem. 2014 May 21;12(19):3021-5. doi: 10.1039/c4ob00139g.
A remarkable α-effect of silicon has been discovered that results in soft nucleophilicity at the Cγ of 3,3-bis(silyl) allyloxy lithium 1. The addition of 1 to α,β-unsaturated carbonyl compounds, including enals, proceeds in a 1,4- over 1,2-manner with medium to good regioselectivity, whereas the parent allyloxy lithium 4 undergoes complete 1,2-addition. The results from DFT calculations of HMPAcomplexed 1 and 4 provide the rationale to explain this different regioselectivity.
已发现硅具有显著的α-效应，该效应导致3,3-双（硅基）烯丙氧基锂1的Cγ处具有软亲核性。将1加成到包括烯醛在内的α,β-不饱和羰基化合物中，以1,4-加成而非1,2-加成的方式进行，区域选择性中等至良好，而母体烯丙氧基锂4则完全进行1,2-加成。对与HMPA络合的1和4进行DFT计算的结果为解释这种不同的区域选择性提供了理论依据。
