Lloyd J. Dolby

New reactions of 3-vinylindoles☆

Abstract The conversion of 5-methyl-2,3,4,6,7,12-hexahydroindolo[2,3-a] quinolizinium iodide ( 3 )_ into 1,2-dimethyl-3-(2-indolycarbonyl) piperidine ( 4 ) is described along with subsequent transformations of 4 and related compounds. A reaction scheme is proposed for this transformation and is supported by a carbon-14 tracer experiment and model studies. Several transformations were encountered in which 3-vinylindoles undergo nucleophilic addition to the vinyl group to give products in which the nucleophile is attached to the C atom adjacent to the indole nucleus.

The C—D ring cleavage of dihydrocorynantheine derivatives : The partial synthesis of dihydroburnamicine

Abstract Two methods are described for the preparation of 3,4- seco -dihydrocorynantheine derivatives bearing an oxygen function at C-3. The first is the cyclization by Ac 2 O-AcONa of dihydrocorynantheic acid and its derivative lacking the methoxymethylene group. This cyclization yields acetoxylactams in which lactam formation has taken place between N b and the carboxyl group accompanied by cleavage of the C-3 N b bond with the introduction of an acetoxy group at C-3. The structures of the lactams are supported by spectroscopic evidence and degradative studies. The second method required 7-acetoxy-7H-dihydrocorynantheine methiodide prepared by treating dihydrocorynantheine successively with lead tetraacetate and methyl iodide. 7-Acetoxy-7H-dihydrocorynantheine-N b -methiodide is converted by the action of hot aqueous acetic acid-sodium acetate and extraction from strongly basic solution to 3-keto-3,4- seco -N b -methyldihydrocorynantheine. Dihydroburnamicine was obtained by a three-step sequence from 3-keto-3,4- seco -N x -methyldihydrocorynantheine and its mass spectrum is reported.

Structure and reactivity of highly substituted cyclobutyl tosylates

Abstract The solvolyses, in 80% aqueous ethanol, of cis- and trans-3-hydroxy-2,2-4,4-tetramethylcyclobutyl tosylates and of cis- and trans-3-hydroxy-2,2,3,4,4-pentamethylcyclobutyl tosylates have been studied. The observed rate differences are explained in terms of steric effects on the transition states for the reactions.