Heterocycles

Reduction of indigo: Simple syntheses of 3-acetoxy-, 1-acetyl-2.3-dihydro-, 3-acetoxy-3′-acetyl-, 3-acetoxy-1, 3′-diacetyl-2, 2′-bisindoles, and 2, 2′-bisindole

M Somei, H Hayashi, S Ohmoto

Index: Somei, Masanori; Hayashi, Hiroyuki; Ohmoto, Shinobu Heterocycles, 1997 , vol. 44, # 1 p. 169 - 176

Full Text: HTML

Citation Number: 10

Abstract

抄録: Indigo was converted to 2, 2′-bisindole by the direct reduction with zinc in acetic acid and acetic anhydride under argon or hydrogen atmosphere. Reduction with tin and iron afforded 3-acetoxy-2, 2′-bisindole predominantly. Useful building blocks such as 1-acetyl- 2, 3-dihydro-, 3-acetoxy-3′-acetyl-, and 3-acetoxy-1, 3′-diacetyl-2, 2′-bisindoles were also produced depending on metal and reaction conditions.