Expedient synthesis of indoles from N-Boc arylhydrazines

Tetrahedron Letters

Volumn 45, Issue 9, 2004, Pages 1857-1859

  Lim, Young Kwan ^a   Cho, Cheon Gyu ^a  

^a Hanyang University   (South Korea)

Author keywords

Fischer indole synthesis; Indoles; N Boc arylhydrazines

Indexed keywords

ACID; BENZOPHENONE DERIVATIVE; HYDRAZINE DERIVATIVE; HYDRAZONE DERIVATIVE; INDOLE DERIVATIVE; KETONE; ORGANIC COMPOUND; WATER;

ARTICLE; CYCLIZATION; HEATING; SCALE UP; SYNTHESIS;

EID: 1242338928     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/j.tetlet.2004.01.011     Document Type: Article

References (12)

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12. Representative procedure: A mixture of N-Boc phenyl hydrazine ( 1a , 50 mg, 0.24 mmol), cyclohexanone (35 mg, 0.36 mmol), TsOH monohydrate (274 mg, 1. 44 mmol) in 3 mL of EtOH was heated under reflux for 1 h. The reaction mixture was then concentrated and filtered through a plug of silica gel to give 37 mg of 3 in 89% yield.