Arenetricarbonylchromium complexes in the synthesis of 6,7-benzomorphanes

Abstract

The action of sodium amide on tricarbonyl-η 6-[1′,2′,3′,4′-tetrahydro-spiro(1,3-dioxolane-2,1′-naphthalene)]chromium followed by reaction with sodium bromoacetate gives tricarbonyl-η 6-[1-(1,2,3,4-tetrahydro-4-oxonaphthalene)acetic acid]chromium ( 4). Some procedures to transform 4 into 1-( N-benzyl-2-aminoethyl)-1,2-dihydronaphthalene ( 10)—a synthon to 6,7-benzomorphanes—are described. Cyclization of 10 by action of mercury(II) acetate yields 3-benzyl-1,2,3,4,5,6-hexahydro-1-hydroxy-2,6-methano-3-benzazocine ( 11).