Regioselective propargylation of aldehydes using potassium allenyltrifluoroborate promoted by tonsil
摘要:
The propargylation of aldehydes using potassium allenyltrifluoroborate promoted by tonsil, an inexpensive and readily available clay, in a chemo- and regioselective way is described. The method is simple and avoids the use of air and moisture sensitive organometallics and products were obtained in good to moderate yields. (C) 2016 Elsevier Ltd. All rights reserved.
Synthesis of Cyclobutanones<i>via</i>Gold-Catalyzed Oxidative Rearrangement of Homopropargylic Ethers
作者:Mei Xu、Tian-Tian Ren、Kai-Bing Wang、Chuan-Ying Li
DOI:10.1002/adsc.201300227
日期:2013.9.16
of a gold catalyst and 8‐ethylquinoline N‐oxide, a homopropargylic ether bearing an electron‐rich aromatic ring or an alkenyl group can be converted into a cis‐cyclobutanone smoothly. An α‐oxo gold carbenoid is proved to be the key intermediate, and it can evolve into an oxonium ylide.
Efficient method for propargylation of aldehydes promoted by allenylboron compounds under microwave irradiation
作者:Jucleiton J R Freitas、Queila P S B Freitas、Silvia R C P Andrade、Juliano C R Freitas、Roberta A Oliveira、Paulo H Menezes
DOI:10.3762/bjoc.16.19
日期:——
The propargylation of aldehydes promoted by microwaveirradiation using allenylboron compounds in a chemo- and regioselective way is described. The corresponding products were obtained in short reaction time, high yield and purity without the need of any solvent when allenylboronic acid pinacol ester was used, or using a minimal amount of acetone when potassium allenyltrifluoroborate was used.
Efficient Propargylation of Aldehydes and Ketones Catalyzed by Titanocene(III)
作者:José Justicia、Iris Sancho-Sanz、Enrique Álvarez-Manzaneda、J. Enrique Oltra、Juan M. Cuerva
DOI:10.1002/adsc.200900479
日期:2009.10
We describe a novel method for the propargylation of a wide range of aldehydes and ketonescatalyzed by titanocene(III) complexes under mild reaction conditions and compatible with many functional groups. Homopropargylic alcohols are obtained as the sole products even when ketones are used as starting materials, which is unusual in Barbier-type propargylations.
A Combined Experimental and Density Functional Theory Study on the Pd-Mediated Cycloisomerization of o-Alkynylnitrobenzenes - Synthesis of Isatogens and Their Evaluation as Modulators of ROS-Mediated Cell Death
作者:Chepuri V. Ramana、Pitambar Patel、Kumar Vanka、Benchun Miao、Alexei Degterev
DOI:10.1002/ejoc.201000769
日期:2010.11
nitro–alkyne cycloisomerization leading to isatogens. Since the first documentation of this reaction by Baeyer (picture of Baeyer and the corresponding literature citation are shown) in the late 19th century, a mild and general method for the synthesis of isatogens has been sought. The electrophilic PdII halide complexes are found to bring about this cyclization to provide the desired isatogens and accommodate
Scalable Regioselective and Stereoselective Synthesis of Functionalized (<i>E</i>)-4-Iodobut-3-en-1-ols: Gram-Scale Total Synthesis of Fungal Decanolides and Derivatives
作者:Alexander M. Sherwood、Samuel E. Williamson、Stephanie N. Johnson、Anil Yilmaz、Victor W. Day、Thomas E. Prisinzano
DOI:10.1021/acs.joc.7b02324
日期:2018.1.19
A reliable protocol to synthesize both racemic and chiral (E)-4-iodobut-3-en-1-ols from aldehydes or epoxides, respectively, containing various aromatic and aliphatic substitutions has been established. The utility of these compounds was then demonstrated by providing access to known fungal decanolides as well as novel aromatic macrocycles. The protocol provided a gram-scale route to (−)-aspinolide