Me<sub>2</sub>Zn-Mediated Addition of Acetylenes to Aldehydes and Ketones
作者:Pier Giorgio Cozzi、Jens Rudolph、Carsten Bolm、Per-Ola Norrby、Claudia Tomasini
DOI:10.1021/jo050115r
日期:2005.7.1
Contrary to expectations, commercially available 2 M Me2Zn in toluene is able to promote the addition of phenylacetylene to aldehydes and ketones. This reactivity is determined by a new, unprecedented mechanism, which involves activation of the zinc reagent via coordination with carbonyl substrates that behave “ligand like”. Broad scope, high tolerance to functional groups, and a simple procedure make
与预期相反,在甲苯中可商购的2 M Me 2 Zn能够促进将苯乙炔添加到醛和酮中。这种反应性是由一种新的,前所未有的机制决定的,该机制涉及通过与表现为“配体样”的羰基底物的配位来激活锌试剂。宽泛的范围,对官能团的高度耐受性以及简单的操作步骤使这种新方法对于合成化学家而言非常有趣。
Brønsted Acid Catalyzed C3-Selective Propargylation and Benzylation of Indoles with Tertiary Alcohols
A Brønsted acid catalyzed C3-selective tert-alkylation of indoles using tertiary propargylic and benzylic alcohols has been developed. New C3-propargylated indole derivatives with a quaternary carbon at the propargylic position have been efficiently synthesized. Reactions were performed in air with undried solvents, and water was the only side product of the process.
Lewis Acid-Catalyzed Cyclization of Enaminones with Propargylic Alcohols: Regioselective Synthesis of Multisubstituted 1,2-Dihydropyridines
作者:Yushang Shao、Kai Zhu、Zhengchen Qin、Ende Li、Yanzhong Li
DOI:10.1021/jo4005553
日期:2013.6.7
A highly efficient BF3·Et2O-catalyzed cascade reaction of enaminones with propargylicalcohols under mild reaction conditions has been developed. This methodology offers regioselective access to multisubstituted 1,2-dihydropyridines in good to excellent yields.
Palladium catalyzed regioselective elimination–hydrocarbonylation of propargylic alcohols
作者:Yuan Yuan、Minqiang Jia、Wanli Zhang、Shengming Ma
DOI:10.1039/c9cc03262b
日期:——
A straightforward approach to synthesizing substituted 1,3-alkadien-2-yl carboxylic acids starting from readily available propargylicalcohols was developed. Based on mechanistic studies, the reaction was found to proceed via regioselective hydrocarbonylation of the C–C triple bonds of the in situ formed 1,3-enyne intermediates, providing 1,3-alkadien-2-yl carboxylic acids with a very high selectivity
Zn(Salen)-Catalyzed Asymmetric Alkynylation of Ketones
作者:Tsutomu Katsuki、Bunnai Saito
DOI:10.1055/s-2004-829057
日期:——
An in situ generated Zncomplex of salen ligand 4 was found to serve as an efficient catalyst for asymmetric addition reaction of an alkynylzinc reagent to various ketones. For example, addition of phenylacetylene to 3,3-dimethyl-2-butanone using the Zncomplex as catalyst showed enantioselectivity as high as 91% ee.