Synthetic, Chemical, and Pharmacological Studies

The fascinating intramolecular mechanism of 3a-tropanol (but not of 3/8) with benzoyl chloride involving H-transfer has now been published in detail. 

Cocaine served as an intermediate in the synthesis of the homotropane anatoxin-a (13b). Anhydroecgonine was converted into the methylketone (11), which was treated with trimethylsulphoxonium methylide the resultant endo cyclopropane (12b) was subsequently photolysed. Ring cleavage could also be 

Campbell, O. E. Edwards, and R. Kolt, Canad. J. Chem., (in press) private communication to B. Witkop. 

Tropaquinuclidine (18) has been synthesized from 3-tropanecarboxylic acid via 3 -tropanylmethylchloride. Tropanehydroquinuclidine (21) was obtained by keto-ester condensation of (19) to (20) and subsequent deoxygenation of the ring to (21). 

Cyclization of the carboxylic acids (22) gave ketones (23a) which, through reaction of the dithioketals with diborane, gave rise to local anesthetic activity.  

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