A synthesis of heteroaromatic analogues of 1-methyl-1, 2, 3, 4-tetrahydroisoquinoline using the pummerer-type cyclization reaction: Observation of tandem cyclization …

Y Horiguchi, K Ogawa, T Saitoh, T Sano

Index: Horiguchi, Yoshie; Ogawa, Keita; Saitoh, Toshiaki; Sano, Takehiro Chemical and pharmaceutical bulletin, 2004 , vol. 52, # 2 p. 214 - 220

Full Text: HTML

Citation Number: 6

Abstract

The sulfoxides 7b and 7d carrying thiophene or benzothiophene as heteroaromatic nucleophiles, when treated with trifluoroacetic anhydride at room temperature (Pummerer reaction), underwent an intramolecular alkylation in an exclusive manner to yield 4, 5, 6, 7- tetrahydro-7-methyl-4-phenylsulfanylthieno [2, 3-c] pyridine-6-carbaldehyde (10) and the corresponding benzothiophene derivative (12b) in high yields, respectively. Thus, this ...