ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
(-)-Cannabidiol has been synthesized from (+)-cis- and (+)-trans-p-menthadien-(2, 8)-ol-(1) and olivetol, using N, N-dimethylformamide dineopentyl acetal or weak acids, such as oxalic, picric, or maleic acid, as catalysts.Since the chirality of (+)-trans-p-menthadien-(2, 8)-ol-(1) is known, the above synthesis constitutes an unambiguous prove for the absolute configuration of (-)-cannabidiol and the two isomeric (-)-6a, 10a-trans-tetrahydrocannabinols.If stronger acids, such as p-toluenesulfonic, trifluoroacetic, or hydrochloric acid, are used as mediators for the reaction, (-)-Δ8-6a, 10a-trans-tetrahydrocannabinol is obtained as the main product.Transformation of the thermodynamically more stable Δ8-tetrahydrocannabinol into the less stable Δ9-isomer was achieved in a practically quantitative yield by addition of hydrochloric acid and elimination of the elements of hydrochloric acid by means of potassium t-amylate. If resorcinols I were used instead of olivetol in the condensation reaction with strong acids, the corresponding homologues of Δ8-tetrahydrocannabinol were obtained in varying yields.
Additional Material:
7 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19690520427
Permalink