PRODUCTION OF SUBSTITUTED INDOLENINE

摘要

PROBLEM TO BE SOLVED: To obtain the subject compound using inexpensive materials in a short step in high yield without causing safety and hygienic problems by reacting a specific ketone with a compound obtained by the specific treatment of a specific aromatic amine. SOLUTION: An aromatic amine of the formula I (X is H, a halogen, a straight or branched-chain alkyl which may have substituent, etc.) (e.g. p- anisidine) is converted to an acidic salt, the salt is diazotized and reacted with a reducing agent and an acidic substance and the product is neutralized to obtain a reaction product. The objective substituted indolenine of the formula III can be produced by reacting the above reaction product with a ketone having secondary C atom at theα-position and expressed by the formula II (R1 to R3 are each an alkyl, an aryl or a cycloalkyl; R2 and R3 may be bonded together to form a 5- or 6-membered ring structure) (e.g. 3-methyl-2-heptanone) in the presence of an acid catalyst.