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2'-amino derivative. In addition, (10) or (19.6) has been totally synthesized from 3,4-dihydro-7-methoxy-1 -methyl-2( 1H) naphthalenone (11)(8) in the same manner as described for (9) from (13) (Fig. 2) and from y-picoline methiodide or methobromide (14.1) and /»-methoxybenzylmagnesium chloride (sequence I, Fig.3)(7).f Alternatively'9,10, (14.1) was reduced (se-quenceII)to 1,4-dimethyl-l,2,5,6,-tetrahydropyridine (17.1) which wasquater-nized to (18.5) with /»-methoxybenzyl chloride. Treatment of (18.5) with ethereal phenyllithium caused rearrangement of the /»-methoxybenzyl radical from nitrogen to adjacent carbon of the pyridine moiety (Stevens rearrangement) (9) giving 2-p-methoxybenzyl-1,4-dimethyl-l,2,5,6,-tetrahydropyridine (16.5) identical with that encountered in sequence I. Cyclization of (16.5) afforded (19.6), 0-demethylation occurring simultaneously with ring closure. By sequence II, 5-ethyl- (19.8)(10), and 5-propyl-(19.10)°° 2'-hydroxy-2-methyl-6,7-benzomorphans have been synthesized from (14.2) and (14.3) in overall yields of 20-30 per cent.

2. a- AND /5-5,9-DlALKYL-2(iV)-METHYL-6,7-BENZOMORPHANS

In comparing some of the more intimate structural features of 2'-hydroxy-2,5-dimethyl-6,7-benzomorphan (10, 19.6) with 3-hydroxy-iV-methylmor-phinan (2), one observes that stereochemical^, (10) mimics (2) at asymmetric carbons 5 and 1 (13 and 9 in compound 2). The introduction of a methyl group at position 9 of compound 10 would provide a third asymmetric centre and would afford the molecule, 2'-hydroxy-2,5,9-trimethyl-6,7-benzomor-phan (20) in which there is complete stereochemical approximation of (2).

Attempts to synthesize such a compound without the phenolic hydroxyl, 2,5,9-trimethyl-6,7-benzomorphan, (23) from the methyl ketone (22) by the method outlined in Fig. 2 were fruitless(12).

0 NMe2

0 NMe2

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