No abstract

We discovered that a reagent comprising a combination of PhBCl 2 and nitriles was useful for syntheses of both 3-acylindoles and 1-(1H-indol-3-yl)alkylamine from indoles. The reaction proceeded selectively at the 3-position of indoles providing 3-acylindoles in moderate to high yields on treatment with the above reagent. Furthermore, the reaction provided the corresponding amine products in moderate to high yields after the intermediate imine was reduced by NaBH 3 CN. These reactions proceeded under mild conditions and are applicable to the formation of indoles functionalized at the 3-position.Key words boron Lewis acid; nitrile; indole; 3-acylindole; 1-(1H-indol-3-yl)alkylamine Sugasawa et al. reported that aniline underwent FriedelCrafts type acylation with nitrile in the presence of BCl 3 .

MIZOI, K.; MASHIMA, Y.; KAWASHIMA, Y.; TAKAHASHI, M.; MIMORI*, S.; HOSOKAWA, M.; MURAKAMI, Y.; HAMANA, H.; Chem. Pharm. Bull. 63 (2015) 7, 538-545, http://dx.doi.org/10.1248/cpb.c15-00157 ; Fac. Pharm., Chiba Inst. Sci., Choshi, Chiba 288, Japan; Eng.) -B. Mosebach 47-126