KEITHS.BROWN,JR.,
4424
AND
T h e trans isomer XVIa showed m.p. 134-137", [a]Z"D-65" (c 1.60), A,, 5.86 (s), 6.09 ( s ) , and fingerprint bands a t 7.43, 8.48, 8.66, 8.77, 9.20, 9.87, and 10.12 p ; n.m.r. 4.35 ( l H , quart e t , J 7 c./sec.; =CHCHa), 7.62 (3H, unsplit; X-methyl), 7.92 ( 3 H , doublet, J 7 c./sec.; =CHCH3); 8.77, 9.08 ( 6 H , two sharp peaks; 2 tertiary C-methyl), 9.21 ( 3 H , doublet, J 7 c./sec.; secondary C-methyl), 9.33, and 9.69 7 (2H, AB doublets, J 4 c./sec. ; cyclopropyl methylene). T h e czs isomer X V I b showed m.p. 149-152", [ a I z 1-83' ~ (c 2.00), A,, 5.86 ( s ) , 6.09 (s, and stronger than for XL'Ia), and fingerprint bands a t 7.82, 8.40, 8.60, 8.76, 9.14, 9.72, 10.17, and 11.61 p ; n.m.r. 3.53 ( l H , quadruplet, J 7 . 5 c./sec.; =CHCH2), 7.60 ( 3 H , unsplit; N-methyl), 8.19 ( 3 H , doublet, J 7.5 c./sec.; =CHCHa), 8.68, 9.05 ( 6 H , two sharp peaks; 2 tertiary C-methyl), 9.19 ( 3 H , doublet, J 7 c./sec.; secondary Cmethyl), 9.34, and 9.67 T ( 2 H , AB doublets, J 4 c./sec.; cyclopropyl methylene). These isomers were readily interconvertible in base; either one gave a n equilibrium mixture of 55-70Yc czs isomer. T h e mixture showed A"?: 244 mp, log e 3.89 (in accord with structure XVI), and gave a strongly positive Zimmermann testz6( X ~ B ~ H - ' a a H 540 mp, hence probably the source of the shoulder in the spectra of the Zimmermann test products from the ketones XVa and XVd). T h e &-benzoyl derivative mixture was produced with benzoyl chloride and potassium carbonate in benzene, and separated on column C ; the t u o isomers were crystallized from a small volume of ethyl ether.
[CONTRIBUTIOS FROM
THE
S.MORRISKUPCHAN
The trans-N-benzoyl derivative (Rf 0.62) showed m.p. 223227O, A, 5.85 ( s ) , 6.09 (s), 6.20 ( v s ) , and fingerprint b i n d s a t 7.28, 8.48, 8.64, 8.73, 9.03, 9.20, 9.87, 10.11, and 13.53 p . .Anal. Calcd. for CalHJ102S: C , 81.03; H , 8.99; N,3.05. Found: C,80.77; H , 9 . 0 7 ; X, 3.44. The cis-N-beazoyl derivative (Rf 0.53) showed m . p . 2:)3-20L0, [ a I z 2-93" ~ ( c 1.63); A, 5.34 ( s ) , 6.09 ( s ) , 6.20 ( v s ) , and fingerprint bands a t 7.26, 7.33, 3.40,8.60,8.72, 9.10, and 10.15 p . .Anal. Calcd. for CI1H4lOnX: C , 81.00; H , 8.93; N, 3.05. Found: C , 80.62; H , 9.03; X, 3.39. The isomers of the 9-benzoyl derivative were si.nilarly readily interconvertible by bise t r e i t m e n t .
N-Benzoyldihydro-des-N'-16-dehydrodihydrocyclobuxine (XVII).-trans-S-Benzoyl-des-S'-l6-dehydrodihydrocycl~bu~it1e (50 mg.) was hydrogenated with reduced p1atinu.n oxide ( 2 5 ing.) in lOvo ethanolic acetic acid (80 m l . ) ; uptake of hydrogen was 1.03 mole equiv. in 30 min. T h e product ( 5 5 ing.), recovered as for dihydrocyclobuxine, was purified on coluinn C ; crystallization of the Rf 0.63 b i n d (27 mg.) f r o n ethanol gave 20 mg., 1n.p. 220-233", [ C X ] ~ ' D-109" ( c 0.53); A, 5.79 (s) and 6.20 (vs) w . A
