Premium
Two robust, efficient syntheses of [ phenyl ring ‐U‐ 14 C]indole through use of [ phenyl ring ‐U‐ 14 C]aniline
Author(s) -
Wager Carrie A. B.,
Miller Sandra A.
Publication year - 2006
Publication title -
journal of labelled compounds and radiopharmaceuticals
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.432
H-Index - 47
eISSN - 1099-1344
pISSN - 0362-4803
DOI - 10.1002/jlcr.1067
Subject(s) - aniline , chemistry , indole test , alkylation , ring (chemistry) , imine , acetaldehyde , organic chemistry , medicinal chemistry , combinatorial chemistry , stereochemistry , catalysis , ethanol
Two robust, efficient syntheses of [ phenyl ring‐ U‐ 14 C]indole are presented. In the first synthesis, we developed optimum reaction conditions for the Houben–Hoesch alkylation of chloro acetonitrile with aniline. This was found through the screening of several Lewis acids coupled with the use of Sugasawa conditions for ortho direction. Following alkylation, the resultant imine was hydrolyzed to the phenone, and then thermal cyclization followed by reduction led to indole. In the second synthesis of [ phenyl ring‐ U‐ 14 C]indole, we utilized microwave‐enhanced conditions for the key coupling. In this transformation, aniline was alkylated with the acetal of bromo acetaldehyde. The mono‐alkylated aniline was then transformed in a straightforward manner to indole. Copyright © 2006 John Wiley & Sons, Ltd.