5-Allyl-9-oxobenzomorphans. Part 2. The Crystal and Molecular Structure of an Unusual Product of Dequaternization of 5-Allyl-9-oxobenzomorphan Methobromide

Abstract

The synthesis of 5-allyl-2'-methoxy-9-oxo-6,7-benzomorphan (5b) is described. The 10-hydroxy-2-methyl-1,11-propano-9H-indeno-1,2,10,11-tetrahydro[2,1-c]pyridine (7a) and the corresponding 6-methoxy derivative (7b) are unexpected products of pyrolysis of 5-allyl-2-methyl-9-oxobenzomorphan methobromide (4a) and 5-allyl-2′-methoxy-2-methyl-9-oxobenzomorphan methobromide (4b) respectively. The molecular structure of 7a (C16H19NO) has been determined from spectral and microanalytical data, and confirmed by X-ray single crystal analysis on its hydrobromide salt using the heavy atom technique. The crystals of [C16H20NO]+Br− are monoclinic, P21/a, with a = 13.724(2), b = 14.022(3), c = 7.495(2) Å, β = 97.33(5)°, and Z = 4. The crystal structure has been refined by block-diagonal least-squares calculations to R and Rw = 0.036 for the 2197 observed reflections. The N atom has planar trigonal coordination, and forms one double and two single C—N bonds of lengths 1.273(4), 1.465(4), and 1.474(4) Å, respectively. The Br is hydrogen-bonded to O. The N and O atoms are trans.

5-Allyl-9-oxobenzomorphans. 3. Potent narcotic antagonists and analgesics-antagonists in the series of substituted 2',9.beta.-dihydroxy-6,7-benzomorphans

“…These rigid molecules possessed functionalities at positions 7 and 8 which were manipulated to produce compounds of still further complexity. In addition, variations at other positions of 1 were made and their effects on biological activity studied. While the hoped for separation of effects may not have been fully realized, compounds of extremely high potency were found.…”

Benzomorphans: synthesis, stereochemistry reactions, and spectroscopic characterizations

“…However, all attempts to prepare the 12-methylene derivatives 166 by dehydration of 35 This method was also successfully applied to the benzomorphan analogue. This approach avoids the formation of ring-opened products such as 163.…”