6,8-DIBROMO-2H-CHROMENE-3-CARBALDEHYDE synthesis

Yield:-

Reaction Conditions:

with potassium carbonate in 1,4-dioxane; for 2 h;Reflux;

Steps:

5.2. General experimental procedure for the synthesis of 2H-chromene-3-carbaldehyde derivatives 18(a-m) and 2-phenyl-2H-chromene-3-carbaldehyde derivatives 18'(a-f)

General procedure: The starting materials used in the reaction comprise of 2H-chromene-3-carbaldehyde derivatives 18(a-m) and 2-phenyl-2Hchromene-3-carbaldehyde derivatives 18'(a-f). Initially, the reaction between salicylaldehydes 16 and acrolein 17 using K₂CO₃ under refluxing dioxane for 2 h afforded 2H-chromene-3-carbaldehyde derivatives 18(a-m) in good to excellent yields. On the other hand, salicylaldehydes 16 on treatment with cinnamaldehyde 17' in the presence of pyrrolidine in DMSO at a room temperature for 12-18 h afforded the 2-phenyl-2H-chromene-3-carbaldehydes 18'(a-f) in a good to excellent yields via oxa-Michael aldol reaction (Scheme 2)

References:

Mishra, Deepak Ranjan;Panda, Bhabani Shankar;Nayak, Sabita;Rauta, Naresh Kumar;Mohapatra, Seetaram;Sahoo, Chita Ranjan;Padhy, Rabindra Nath [Tetrahedron,2022,vol. 124,art. no. 133015]