Zincate-mediated rearrangement reaction of 2-(1-hydroxyalkyl)-1-alkylcyclopropanol
作者:Kenichi Nomura、Seijiro Matsubara
DOI:10.1039/b901043b
日期:——
A rearrangement of lithium alkoxide of 2-(1-hydroxyalkyl)-1-alkylcyclopropanol into lithium alkoxide of vic-diol was mediated with an organozincate complex.
Enantioselective Synthesis of 2-Methyl-1,2-<i>syn</i>- and 2-Methyl-1,2-<i>anti</i>-3-butenediols via Allene Hydroboration−Aldehyde Allylboration Reaction Sequences
作者:Ming Chen、Masaki Handa、William R. Roush
DOI:10.1021/ja904599h
日期:2009.10.21
The hydroboration of allene 7 with ((d)lpc)(z)BH at 0 degrees C provides the kinetic allylborane 12Z with >20:1 selectivity. However, when the hydroboration is performed at 85 degrees C, the kinetically formed allylborane isomerizes to give the thermodynamic allylborane 12E with >= 12:1 selectivity. Subsequent treatment of 12Z or 12E with aldehydes at -78 degrees C, followed by oxidative workup, provides the 2-methyl-1,2-diols 8 and 9 in good yield and with 80-92% e.e.
Zn/InCl<sub>3</sub>-Mediated Pinacol Cross-Coupling Reactions of Aldehydes with α,β-Unsaturated Ketones in Aqueous Media
作者:Yong-Sheng Yang、Zhi-Liang Shen、Teck-Peng Loh
DOI:10.1021/ol900619d
日期:2009.5.21
A zinc/indium chloride-mediated pinacol cross-coupling reaction between aldehyde and alpha,beta-unsaturated ketone in aqueous media was developed. The 1,2-diols were obtained in moderate to good yields with up to 93:7 diastereoselectivity.
A New Zincate-Mediated Rearrangement Reaction of 2-(1-Hydroxyalkyl)-1-alkylcyclopropanol
作者:Kenichi Nomura、Seijiro Matsubara
DOI:10.1002/chem.200901054
日期:2010.1.11
A novel rearrangement of 2‐(1‐hydroxyalkyl)‐1‐alkylcyclopropanol has been found. It proceeds in the presence of a catalytic amount of organozinc ate complex to give vic‐diols. The rearrangement can be applied to various types of 2‐(1‐hydroxyalkyl)‐1‐alkylcyclopropanol, which can be easily prepared from the corresponding α,β‐epoxyketones and bis(iodozincio)methane. When bicyclo[13.1.0]pentadecane‐1