• Synthesis of 2-substituted benzo[b]thiophene derivatives were earlier from the acylation of benzo[b]thiophene using acyl source like acetyl chloride, acetic anhydride, 2-oxocarboxylic acid, N, N-dimethylacetamide, acetaldehyde and benzoyl chloride.
• These reactions yielded major amount of 3-substituted & minor amount of 2-substituted benzo[b]thiophenes due to the high reactivity of C-3 than C-2 position of benzo[b]thiophene.
• Expensive starting materials, handling of butyl lithium, high temperature, inert atmosphere, synthesized beta zeolite to utilize for the industrial scale preparation of 2-substituted benzo[b]thiophene will be very difficult.
• Further a few Non-patent literatures discussed regarding the developing of the catalyst using synthesis with other associated issues.
• Present invention has addressed said issues efficiently.

• Present invention describes one step synthesis of 2-substituted benzo[b]thiophene.
• The General formula includes

The process explains in smart chart herein:

• The synthesis of 2-substituted benzo[b]thiophenes is by reacting the starting materials substituted or unsubstituted 2-halogenobenzaldehyd;
• substituted or unsubstituted acetyl/phenacyl bromide with a catalyst, a sulphur source and phase transfer catalyst in an aqueous medium;
• Said aqueous medium with atmospheric air and at temperature in the range of 25°C- 30°C.