4006
J. Org. Chem. 1988,53, 4006-4014
(CDCl,) 6 19.3, 25.1, 125.8, 126.7, 127.7, 129.7, 130.4, 130.6, 130.8, 131.2,132.5, 132.7, 133.2, 137.4,143.4,157.9, 183.8; IR (CClJ 1669.5 (C=O) cm-'; MS (70 eV), m/e (relative abundance) 138 (loo), 193 (loo), 199 (100); molecular ion calcd for Cl7H1,Nz0 m/e 262.1106, found 262.1105. Isopropyl ether: 'H NMR (CDC13)6 1.07 (d, J = 6.0 Hz, 6 H, methyl), 3.76 (m, J = 6.0 Hz, 1 H, methine), 5.74 (9, 1 H, CHOR). (b) In tert-Butyl Alcohol. DAAN (55 mg, 0.25 mmol) was dissolved in 50 mL of tert-butyl alcohol; two 25-mL aliquots were treated as described above. Photolysis to 83% completion afforded bianthronyl(39%), anthrone (
