RITTER REACTIONS .9. TRANSANNULAR ADDITION OF NITRILES TO THE 5H-DIBENZO[A,D]CYCLOHEPTENE RING-SYSTEM

The 5H-dibenzo[a,d]cyclohepten-5-ols (1a-e) undergo sequential intramo lecular and conventional Ritter reactions with acetonitrile to afford the heno)-5H-dibenzo[a,d]cy-clohepten-11-yl}acetamides (6a-e). Typical yields for these one-flask conversions are 52-64%, except for the rea ction of (1a) where production of the dimeric substance (4a) is favour ed. Alcohol (1a) can provide either type of product in good yield, dep ending on the conditions employed, when reacted with benzonitrile. The molecular skeleton present in the adducts (6) has been confirmed by d etermination of the crystal structure of (6c) [C25H22N2O, P1BAR, a 9.1 88(3), b 14.632(5), c 16.563(9) angstrom, alpha 115.64(2), beta 90.92( 2), gamma 96.29(2)-degrees, Z 4, R 0.043].