17324-05-9Relevant academic research and scientific papers
Novel Photochemical Reactions of 1- and 2-Naphthols with Ethylene Promoted by Aluminum Halides
Kakiuchi, Kiyomi,Yamaguchi, Bunji,Kinugawa, Masahiko,Ue, Masaki,Tobe, Yoshito,Odaira, Yoshinobu
, p. 2797 - 2803 (2007/10/02)
Novel photoreactions of 1- and 2-naphthols with ethylene promoted by aluminum halides are described.Irradiation of 2-naphthol (2a) with AlX3 (X=Cl, Br) and ethylene in CH2Cl2 gave the corresponding cycloadduct 7a in good yields.The major side product was 2-ethyl-1-naphthol (8a).Of the Lewis acids and alkenes examined, only AlCl3 and AlBr3 effected the reaction and only ethylene gave satisfactory results, although allene can also be employed.Naphthols 2b-e having different electron-attracting substituents on C-6 afforded adducts 7b-e in moderate to good yields, while the reactions of C-3-alkyl-substituted derivatives 8a and 15b were unsuccessful.By contrast, 1-naphthol (1a) and its derivatives 1b-e exhibited diverse reactivities depending on the substituent on C-2, C-3, or C-6.Namely 1a and 3-methyl derivative 1b afforded cycloadducts 16a and 16b in moderate yields.On the other hand, 2-methyl and 2-propyl derivatives 1c and 1d yielded unusual products like indenones 22a and 22b and cyclopropyl ketones 23a and 23b, respectively. 6-Methoxy derivative 1e also gave indenone 30.Plausible reaction mechanisms leading to the observed products are presented.
Novel photocycloaddition of 2-naphthols to ethylene in the presence of Lewis acid
Ue,Kinugawa,Kakiuchi,Tobe,Odaira
, p. 6193 - 6194 (2007/10/02)
The photoreaction of 2-naphthols 1a-e with ethylene in the presence of aluminum halide gave the [2+2] cycloadducts 3a-e in good yields.
