abstract |
Improved processes for preparing 2'-alkoxy-2,5-di-substituted-9-oxo-6,7-benzomorphans from benz[e]indolines and synthesis of the benz[e]indoline intermediates are described. A representative example involves synthesis of 9b-allyl-8-methoxy-3-methyl-5,9b-dihydrobenz[e]indoline and bromination thereof to 9b-allyl-4-bromo-8-methoxy-2,4,5,9b-tetrahydro-1H-benz[e]indole methylbromide which is then hydrolyzed with a weak base such as ammonium bicarbonate to provide 5-allyl-2'-methoxy-2-methyl-9-oxo-6,7-benzomorphan. |