7898 The structures of 11 and 12 were determined by comparison of ir and nmr spectra with those of 9 and 10. lla: bp83-85'(0.18mm); nmr(CCI4)T4.3-4.9(m, 2H,CH=C and CHOAc), 8.00 (s, 3 H, OCOCH3), 8.08 (s, 3 H, OCOCHI), 8.40 (broad s, 3 H, CHIC f ), 8.56 (s, 3 H, CHI), 8.60(s, 3 H, CH3), 7.7-8.9 (m, 5 H, aliphatic); ir (film) 3025 (HC=), 1730 (C=O), 1450, 1435, 1240 (CO), 1020 (CO), 970, 925, 805 cm-l. Anal. Calcd for C14H~204: C, 66.11; H , 8.72. Found: C, 66.28; H, 8.64. 12a: bp 83-85' (0.18 mm); nmr (CCl,) T 4.2-4.6 (m, 1 H, CH=C
