2-Acyloxy-4,6-dimethoxy-1,3,5-triazine - A New Reagent for Ester Synthesis
作者:Janina E. Kamińska、Zbigniew J. Kamiński、Józef Góra
DOI:10.1055/s-1999-3448
日期:1999.4
2-Acyloxy-4,6-dimethoxy-1,3,5-triazines obtained in reaction between carboxylic acid and 2-chloro-4,6-dimethoxy-1,3,5-triazine were used as acylating agents for the synthesis of esters from primary, secondary, and tertiary alcohols. Because of mild acylation conditions the method could be applied to esterification of labile alcohols with aromatic and aliphatic (also α-branched) acids in good yields.
The Preparation of Optically Active β-Keto Sulfoxides by Means of an Enantiomer-differentiating Reaction of α-Lithio Aryl Methyl Sulfoxides with Chiral Carboxylates
作者:Norio Kunieda、Akira Suzuki、Masayoshi Kinoshita
DOI:10.1246/bcsj.54.1143
日期:1981.4
The reaction of α-lithio aryl methyl sulfoxides with a limited amount of chiral carboxylates (R2–CO–O–R*) was found to be an enantiomer-differentiating reaction, affording the corresponding optically active β-keto sulfoxides (3), together with optically active aryl methyl sulfoxides which have the opposite configuration. The optical purity and the predominant configuration of 3 obtained were assigned
Treatment of (−)-menthyl carboxylates(2) with 2 equiv of p-tolylsulfinylcarbanion(1) afforded the corresponding opticallyactive β-keto sulfoxides(3) together with opticallyactivemethyl p-tolyl sulfoxide. The enantiomeric purity and the predominant configuration of the products were discussed.
A simple and highly efficient protocol for pivaloylation of alcohols without using a catalyst under solvent-free conditions has been developed. The key advantages of the reaction are short reaction time, high yields, simple workup, and no need for further purification. Selectivity was observed between primary alcohols vs. secondary alcohols and aliphatic alcohols vs. aromatic alcohols. The accentuated
Tropolonate Salts as Acyl-Transfer Catalysts under Thermal and Photochemical Conditions: Reaction Scope and Mechanistic Insights
作者:Demelza J. M. Lyons、Claire Empel、Domenic P. Pace、An H. Dinh、Binh Khanh Mai、Rene M. Koenigs、Thanh Vinh Nguyen
DOI:10.1021/acscatal.0c03702
日期:2020.11.6
strong nucleophilicity and photochemical activity, can promote the coupling reaction between alcohols and carboxylic acid anhydrides or chlorides to give products under thermal or blue light photochemical conditions. Kinetic studies and density functional theory calculations suggest interesting mechanistic insights for reactions promoted by this acyl-transfer catalytic system.