J. C. Bardhan

Bio: J. C. Bardhan is an academic researcher. The author has contributed to research in topics: Terpene. The author has an hindex of 1, co-authored 1 publications receiving 3 citations.

Regiospecific gamma-alkylation and acylation of cyclic beta-diketone enol ethers

Abstract: Enol ethers of cyclic β-diketones can be alkylated and acylated in high yields at C(6). When this position is blocked, alkylation takes place at C(2).

The Dieckmann Condensation (Including the Thorpe‐Ziegler Condensation)

Abstract: The Dieckman condensation is an acetoacetic ester condensation in which a dicarboxylic ester is cyclized to a beta-ketonic ester through the action of a base. The dicarboxylic ester must have at least one alpha-hydrogen atom and the carbalkoxy groups must be situated that cyclization will result in a 4-membered ring or larger ring. Discovery and development of the reaction are generally credited to Dieckmann, who found that heating an adipic or a pimelic ester with sodium and a trace alcohol led to cyclization with formation of a cyclopentanone or a cyclohexanone. The Dieckmann condensation has proved useful for the preparation of a variety of carbocyclic and heterocyclic ketones and has been extended to the synthesis of 7 and 8-membered rings. Keywords: Dieckman condensation; cyclizations; Michael condensation; intermolecular ester; alkylation; acyloin condensation; failures

Use of some 2-acetyl-2-cyclohexen-1-one derivatives in the total synthesis of steroids

Abstract: The 3-methoxy- and 3-chloro-2-acetyl-2-cyclohexen-1-ones do not react with carbanions by the substitutive addition scheme under the usual conditions of running condensation of the Michael type.