학술논문
On the allylic hydroxylation of ent-kaurenic acid with SeO2
Document Type
article
Source
Avances en Química, Vol 9, Iss 1, Pp 7-13 (2014)
Subject
Language
English
Spanish; Castilian
Spanish; Castilian
ISSN
1856-5301
Abstract
Allylic hydroxylation of ent-kaur-16-en-19-oic acid (1a) with SeO2 was tried using either dioxane or dichloro-methane as solvents as well as different reagent and reaction time conditions at room temperature. Oxidation of 1a in dioxane with H2O2 decreased reaction time but led to the formation of many by-products on addition to ent-15D-hydroxy-kaur-16-en-19-oic acid (2a), which was the main product. Using dichloromethane as solvent without addition of H2O2 made the reaction slower and yielded mainly 2a (70% at 24 h, 53% at 48 h) and ent-17-oxo-kaur- 15,16-en-19-oic acid (3a,18% at 24 h, 43% at 48 h). The course of the reaction was followed by GC-MS, after methylation of the reaction mixtures.