7‐Methoxyindole and its Derivatives

Abstract

7‐Methoxyindole was prepared by reductive cyclization of 3‐methoxy‐2, β‐dinitrostyrene. The synthesis and pharmacological properties of several 7‐methoxytryptamines are described.

N,N-Diethyl-(R)-[3-(2-aminopropyl)-1H-indol-7-yloxy]acetamide: Its Process Chemistry Ranging from Enantiocontrolled Construction of the Chiral Amine Side Chain to Regioselective Functionalization of the Aromatic Starting Materials

“…With 1-(7-methoxy-1 H -indol-3-yl)-2-nitropropene ( 19 ), its LiAlH 4 -reduction in THF provided saturated primary (±)-amine ( 20 ) in 63% yield, with LiAlH 4 fulfilling the following two tasks in sequence: (1) saturation of the electron-deficient olefin in 19 by conjugate addition of a hydride; and (2) reductive deoxygenation of the resulting aliphatic nitro group to a primary amine function in (±)- 20 (Scheme ). Thus, to avoid the use of expensive pyrophoric LiAlH 4 , reductive conversion of 17 to (±)- 8 was explored in a stepwise manner, which culminated in the following two-step procedures: 7 First, 17 was treated with NaBH 4 (1.0 equiv) in PhMe/MeOH (6:1; 4.5 v/w) with heating at 40 °C for 1 h to give nitroalkane ( 18 ) in 79% yield as a crystalline solid after recrystallization from PhMe/MeOH (10:3; 8.4 v/w relative to 17 ).…”