Photochemical Cyclization of Allylated Anisole and N‐Alkyl Aniline Derivatives. Preliminary communication

The allyl anisole derivatives 1 , d 2 ‐ 1 , 3 , 5 and 7 ( Scheme 1 ), on exposure to UV. light in benzene, acetone or methanol solution, cyclize to yield the corresponding cyclopropyl anisole derivatives 2 , d 2 ‐ 2 , cis ‐ and trans ‐ 4, 6 and 8 , respectively. Under the above conditions the N, N‐dialkyl‐2‐allyl anilines 9 , 10 and 11 give similar results ( Scheme 2 ). On the other hand, N‐alkyl‐2‐allyl anilines ( 15 and 19 , Scheme 3 ) are transformed by UV. light in cyclohexane or benzene solution into 2‐methyl‐indolines ( 16 and 20 , resp.), whereas in methanol solution the corresponding 2′‐methoxy compounds 18 and 21 are formed in addition to 16 and 20 , respectively.