The photochemistry of the enamide system and its useful application have been well investigated;' simple enamides generally undergo a [1,3]-acyl radical shift to afford vinylogous amides Meanwhile, photoisomerizations of 1 -acylindoles of an enamide system have been described to merely provide 3-, 4-, and 6-acylindoles by the usual photo-Fries type of rearrar~gement.~ In this communication, we report the novel photorearrangement synchronized with a conversion of 1-acylindoles la-d to 3-acylindolenines 2a-d, as depicted in Scheme I, which, with R' = CH2CH2NHR2, n = 2,3, was followed by a simultaneous intramolecular ring enlargement to provide the nine-or eight-membered lactams 3a-c in a one-pot reaction, establishing a versatile entry to the total synthesis of a diverse array of Aspidosperma and Strychnos alkaloids. The general synthetic scheme is demonstrated by formula 4 in Scheme 11, with the dotted lines a or b and c.It was discovered by us that the photoisomerization of 5 wtih a 300-W high pressure mercury lamp afforded 6435 [RN-(COR')-CH=CR2R3 -RN=CH-C(COR)R2R3], which is the so far unknown reactive species, together with 7, 8, and 9, the products of the usual isomerization, in addition to the starting material 5 and The remarkable reactivities of the novel [RN(COR')-CH=CHR' -RNH-CH=C(COR')R2].2 (1) Lenz, G. R. Synthesis 1978, 489. (2) Bertele, E.; Boos, H.; Dunitz, J. D.; Elsinger, F.; Eschenmoser, A,; Felner, I.; Gribi, H. P.; Gschwend, H.; Meyer, E. F.; Pesaro, M.; Scheffold, R.
