An extremely mild 3-aza-Claisen reaction. 1. Rearrangement of simple N-allylamides.
摘要:
An extremely mild 3-aza-Claisen reaction has been developed. Readily available N-allyl amides are converted to pentenylnitriles in moderate to good yields by a transformation that occurs at room temperature under essentially neutral conditions.
Selective ammonolysis and aminolysis of dimethyl succinate. Synthesis of optically active N-alkylsuccinimides
摘要:
Candida antarctica lipase catalyzes the selective monoammonolysis and aminolysis of dimethyl succinate with ammonia and aliphatic amines, respectively, in dioxane as solvent. This enzyme shows a high enatioselectivity when racemic amines are used. Optically active amidoesters are also obtained in the reaction of dimethyl succinate with racemic alpha-methylalkylamines in hexane as solvent. In this medium, the enzyme catalyzes the formation of N-alkylsuccinimides or optically active N-alkyl-alpha-methylsuccinimides from dimethyl succinate or alpha-methylsuccinate and amines.
TMSCl Promoted Direct Conversion of Cyclic Anhydrides to (Un)Symmetric‐Diesters/Amide Esters
作者:Meera Johny、Amuda Manikandan、Goreti Rajendar
DOI:10.1002/asia.202301017
日期:2024.2
A mild, novel, and efficient silyl-promoted conversion of cyclic anhydride to diesters and amide esters. The reaction follows a two-step process, ring opening of anhydride by amine or alcohol following esterification. The reaction was carried out in the presence and absence of base. The method has broad substrate scope and is applicable for the synthesis of commercial plasticizers.
An extremely mild 3-aza-Claisen reaction. 1. Rearrangement of simple N-allylamides.
作者:Michael A. Walters、Colleen S. McDonough、Perry S. Brown、Andrew B. Hoem
DOI:10.1016/0040-4039(91)80848-z
日期:1991.1
An extremely mild 3-aza-Claisen reaction has been developed. Readily available N-allyl amides are converted to pentenylnitriles in moderate to good yields by a transformation that occurs at room temperature under essentially neutral conditions.
Selective ammonolysis and aminolysis of dimethyl succinate. Synthesis of optically active N-alkylsuccinimides
Candida antarctica lipase catalyzes the selective monoammonolysis and aminolysis of dimethyl succinate with ammonia and aliphatic amines, respectively, in dioxane as solvent. This enzyme shows a high enatioselectivity when racemic amines are used. Optically active amidoesters are also obtained in the reaction of dimethyl succinate with racemic alpha-methylalkylamines in hexane as solvent. In this medium, the enzyme catalyzes the formation of N-alkylsuccinimides or optically active N-alkyl-alpha-methylsuccinimides from dimethyl succinate or alpha-methylsuccinate and amines.
Rearrangements of Substituted 3-Aza-1,2,5-hexatrienes. 3. The Scope and Versatility of an Extremely Mild 3-Aza-Cope Reaction
作者:Michael A. Walters、Andrew B. Hoem、Colleen S. McDonough
DOI:10.1021/jo951587g
日期:1996.1.1
An investigation of the [3,3]-sigmatropic reaction of substituted 3-aza-1,2,5-hexatrienes to give 4-pentenenitriles is presented. This reaction has been found to occur under a wide variety of reactions conditions (10 are reported) starting from readily available N-allylamides. In contrast to other 3-aza-Cope reactions, this process occurs at room temperature, under essentially neutral conditions, allowing for the facile preparation of substituted nitrile products in moderate to excellent yields. The scope and versatility of this reaction are demonstrated by its use on a wide variety of substrates, including nitrogen- and oxygen-substituted amides. The rearrangements of cis- and trans-4-tert-butyl-N-allylcyclohexanecarboxamides 16a and 16b are reported and were found to give a ratio of axial to equatorial (A:E) products consistent with A:E ratios found for other related sigmatropic reactions. The stereochemical requirements for this reaction appear to be similar to other [3,3]-rearrangements even though the transition state for this rearrangement is most likely neither boat nor chairlike.