Dimethylmalonyltrialkylphosphoranes: probing the steric effect on phosphorus and its stereochemical consequence in esterification reactions of chiral secondary alcohols
High chemical yields and high levels of stereochemical inversion are demonstrated in the phosphorane-mediated esterification reaction of chiral alcohols with non-hindered carboxylic acids through the incorporation of sterically non-hindered alkyl groups of phosphorus.
Dimethylmalonyltrialkylphosphoranes: New General Reagents for Esterification Reactions Allowing Controlled Inversion or Retention of Configuration on Chiral Alcohols
作者:James McNulty、Alfredo Capretta、Vladimir Laritchev、Jeff Dyck、Al J. Robertson
DOI:10.1021/jo026639y
日期:2003.2.1
through reaction of a trialkylphosphine with 2-chlorodimethylmalonate in the presence of triethylamine. These new reagents promote the condensation reaction of carboxylic acids with alcohols to provide esters along with trialkylphosphine oxide and dimethylmalonate. The condensation reaction of chiral secondary alcohols can be controlled to give either high levels of inversion or retention through a
Electrochemically Tuned Oxidative [4+2] Annulation and Dioxygenation of Olefins with Hydroxamic Acids
作者:Bang‐Yi Wei、Dong‐Tai Xie、Sheng‐Qiang Lai、Yu Jiang、Hong Fu、Dian Wei、Bing Han
DOI:10.1002/anie.202012209
日期:2021.2.8
hydroxamic acids with olefins for the synthesis of benzo[c][1,2]oxazines scaffold via anode‐selective electrochemical oxidation. This protocol features mild conditions, is oxidant free, shows high regioselectivity and stereoselectivity, broad substrate scope of both alkenes and hydroxamic acids, and is compatible with terpenes, peptides, and steroids. Significantly, the dioxygenation of olefins employing hydroxamic
Efficient Method for the Preparation of Carboxylic Acid Alkyl Esters or Alkyl Phenyl Ethers by a New-Type of Oxidation–Reduction Condensation Using 2,6-Dimethyl-1,4-benzoquinone and Alkoxydiphenylphosphines
A new-type of oxidation–reduction condensation proceeded smoothly to afford carboxylic acid alkyl esters or alkyl phenyl ethers in good to high yields by combined use of alkoxydiphenylphosphines (1...
Photocatalytic Water‐Splitting Coupled with Alkanol Oxidation for Selective
<i>N</i>
‐alkylation Reactions over Carbon Nitride
作者:Yangsen Xu、Zhaofei Zhang、Chuntian Qiu、Shaoqin Chen、Xiang Ling、Chenliang Su
DOI:10.1002/cssc.202002459
日期:2021.1.21
(PWST) enables the direct use of water as appealing “liquid hydrogen source” for transferhydrogenation reactions. Currently, the development of PWST‐based transferhydrogenations is still in an embryonic stage. Previous reports generally centered on the rational utilization of the in situ generated H‐source (electrons) for hydrogenations, in which photogenerated holes were quenched by sacrificial