A chemoselective deprotection of trimethylsilyl acetylenes catalyzed by silver salts
摘要:
Trimethylsilyl acetylenes can be selectively deprotected in the presence of a catalytic amount of silver salts. AgNO3 and AgOTf proved to be the most effective catalyst in a mixture of methanol, water and dichloromethane. Other functional groups, and especially silyl ethers, are not affected in these conditions. (c) 2005 Elsevier Ltd. All rights reserved.
The Gold-catalyzed Formal Hydration, Decarboxylation, and [4+2] Cycloaddition of Alkyne Derivatives Featuring L<sub>2</sub>/Z-type Diphosphinoborane Ligands
The catalytic formal hydration of alkynes and decarboxylation of alkynoic acid were developed using a Au catalyst featuring a Z-ligand. Furthermore, the intramolecular [4+2] cycloaddition of the al...
使用以 Z 配体为特征的 Au 催化剂开发了炔烃的催化形式水合和炔酸的脱羧。此外,al的分子内[4+2]环加成...
Ir-Catalyzed Regio- and Enantioselective Hydroalkynylation of Trisubstituted Alkene to Access All-Carbon Quaternary Stereocenters
作者:Su-Lei Zhang、Wen-Wen Zhang、Bi-Jie Li
DOI:10.1021/jacs.1c04493
日期:2021.6.30
substrate-directed, iridium-catalyzed enantioselective hydroalkynylations of trisubstituted alkenes to form an acyclic all-carbon quaternary stereocenter β to a nitrogen atom. The hydroalkynylation of enamide occurred with unconventional selectivity, favoring the more hindered reaction site. Homopropargyl amides with β-stereocenters were prepared in high regio- and enantioselectivities. Combined experimental and
Catalytic Anti-Markovnikov Hydrobromination of Alkynes
作者:Mycah R. Uehling、Richard P. Rucker、Gojko Lalic
DOI:10.1021/ja503944n
日期:2014.6.18
We have developed the first catalytic method for anti-Markovnikovhydrobromination of alkynes. The reaction affords terminal E-alkenyl bromides in high yield and with excellent regio- and diastereoselectivity. Both aryl- and alkyl-substituted terminal alkynes can be used as substrates. Furthermore, the reaction conditions are compatible with a wide range of functional groups, including esters, nitriles
Bis(amidate)bis(amido) Titanium Complex: A Regioselective Intermolecular Alkyne Hydroamination Catalyst
作者:Jacky C.-H. Yim、Jason A. Bexrud、Rashidat O. Ayinla、David C. Leitch、Laurel L. Schafer
DOI:10.1021/jo402668q
日期:2014.3.7
o) titanium precatalyst for the anti-Markovnikov hydroamination of alkynes is reported. Hydroamination of terminal and internal alkynes with primary alkylamines, arylamines, and hydrazines is promoted by 5–10 mol % of Ti catalyst. Various functional groups are tolerated including esters, protected alcohols, and imines. The in situ generated complex shows comparable catalytic activity, demonstrating
Enantioselective Total Synthesis of (−)-Acylfulvene and (−)-Irofulven
作者:Dustin S. Siegel、Grazia Piizzi、Giovanni Piersanti、Mohammad Movassaghi
DOI:10.1021/jo901926z
日期:2009.12.18
We report our full account of the enantioselectivetotalsynthesis of (−)-acylfulvene (1) and (−)-irofulven (2), which features metathesis reactions for the rapid assembly of the molecular framework of these antitumor agents. We discuss (1) the application of an Evans Cu-catalyzed aldol addition reaction using a strained cyclopropyl ketenethioacetal, (2) an efficient enyne ring-closing metathesis cascade