N-Heterocyclic Carbene-Catalyzed Internal Redox Reaction of Alkynals: An Efficient Synthesis of Allenoates
摘要:
An efficient N-heterocyclic carbene (NHC)-catalyzed internal redox reaction of alkynals that bear a y leaving group has been developed. This process provides a new access to a range of allenoates in good yields. Preliminary results demonstrate that the enantioselective variant can also be achieved.
Stereoselective Syntheses of Trisubstituted Olefins via Platinum Catalysis: α-Silylenones with Geometrical Complementarity
作者:Douglas A. Rooke、Eric M. Ferreira
DOI:10.1021/ja1058197
日期:2010.9.1
The stereoselective syntheses of alpha-silylenones using catalytic PtCl(2) are reported. Via alkyne activation, alpha-hydroxypropargylsilanes are converted to (Z)-silylenones through a highly selective silicon migration. The complementary (E)-silylenones are accessed by a regioselective hydrosilylation of the ynone precursor. The synthetic utility of these compounds is demonstrated in cross-coupling
Stereoselective Dichlorination of Allylic Alcohol Derivatives to Access Key Stereochemical Arrays of the Chlorosulfolipids
作者:Grant M. Shibuya、Jacob S. Kanady、Christopher D. Vanderwal
DOI:10.1021/ja804167v
日期:2008.9.17
Dichlorination of (Z)-allylic trichloroacetates efficiently and stereoselectively generates the syn,syn hydroxydichloride stereotriad that is prevalent in the understudied polychlorinated sulfolipid class of natural products. Further, the dichlorination of a (Z)-allylic chlorohydrin affords with high selectivity a stereotetrad present in one of the chlorosulfolipids.
Spirodiepoxide-Based Cascades: Direct Access to Diverse Motifs
作者:Rojita Sharma、Madhuri Manpadi、Yue Zhang、Hiyun Kim、Novruz G. Ahkmedov、Lawrence J. Williams
DOI:10.1021/ol201101e
日期:2011.7.1
Allene epoxide formation/opening reaction sequences enabled direct access to diverse products. Described here are a single flask procedure for allene preparation and allene oxidation/derivatization reactions that give, among others, diendiol, diyndiol, alpha'-hydroxy-gamma-enone, dihydrofuranone, butenolide, and delta-lactone products.
<i>N</i>-Heterocyclic Carbene-Catalyzed Internal Redox Reaction of Alkynals: An Efficient Synthesis of Allenoates
作者:Yu-Ming Zhao、Yik Tam、Yu-Jie Wang、Zigang Li、Jianwei Sun
DOI:10.1021/ol300111m
日期:2012.3.16
An efficient N-heterocyclic carbene (NHC)-catalyzed internal redox reaction of alkynals that bear a y leaving group has been developed. This process provides a new access to a range of allenoates in good yields. Preliminary results demonstrate that the enantioselective variant can also be achieved.