Novel reactions of indium reagents with 1,2-diones: a facile synthesis of α-hydroxy ketones
作者:Vijay Nair、C.N Jayan、Sindu Ros
DOI:10.1016/s0040-4020(01)00937-1
日期:2001.11
Indium mediated reactions of allyl, cinnamyl, propargyl and benzyl bromides, ethyl bromoacetate and ethyl-4-bromocrotonate with 1,2-diones, in the presence of sodium iodide, occur efficiently to afford α-hydroxy keto compounds in excellent yields.
Catalytic Asymmetric Synthesis of Vicinal Quaternary Stereocenters Enabled by Alkylation of α,α-Disubstituted Aldehydes with 3-Bromooxindoles
作者:Long-Jun Dong、Qi Wang、Jing-Feng Zhang、Zhen Li、Dao-Yong Zhu、Xiao-Ming Zhang、Yong-Qiang Tu、Shao-Hua Wang
DOI:10.1021/acs.orglett.4c00700
日期:2024.4.19
An organocatalytic enantioselective alkylation of α,α-disubstituted aldehydes with 3-bromooxindoles is reported. Enantioenriched oxindoles with vicinal quaternary stereocenters are accessed by an asymmetric conjugate addition process of branched aldehydes with o-azaxylylene intermediates (indol-2-ones). Key to the success of highly diastereo- and enantioselective transformations is the combined use
Copper(II) Triflate Catalyzed Regioselective and Enantioselective Propargylation of Isatin Derivatives by Using Allenylboronic Acid Pinacol Ester
作者:Naveen Gupta、Rajkumar Tak、Mohd Nazish、Ajay Jakhar、Noor-ul H. Khan、Rukhsana I. Kureshy
DOI:10.1002/ejoc.201701745
日期:2018.3.22
Regioselectivepropargylation of isatins in aqueous media. With this protocol we could achieve propargyl alcohols in high yields with wide substrate scope. The enantioselective version was also explored to yield chiral alcohols with er up to 12:88, which is reported for the first time.
A robust and rapid synthesis of 3-hydroxy-3-alkyl-2-oxindoles from isatins is described. This method introduces an ecofriendly, un-activated Zn dust, solid $$\hbox NH}_4}\hbox Cl}$$ and substrates under aqueous conditions, which has produced the product in moderate to good yields. Without using column chromatography, majority of the compounds were isolated in analytically pure form. The progress of the reaction could be visualized by naked eye. SYNOPSIS A robust and rapid synthesis of 3-hydroxy-3-alkyl-2-oxindoles from isatins is described. This method introduces an ecofriendly method using un-activated Zn dust, solid $$\hbox NH}_4}\hbox Cl}$$ and substrates under aqueous conditions, which has produced the products in moderate to good yields.