Some fatty acids having an O ‐heterocycle in their terminal positions. II . ω‐(3‐Coumarinyl)alkanoic acids and ω‐(2‐chromonyl)alkanoic acids

Some ω‐3‐coumarinyl)alkanoic acids 1a , n = 3‐6 were synthesized by cyclization of corresponding ethyl o ‐formylphenyl alkanedioate 3 with DBU followed by hydrolysis. By a similar cyclization, some ω‐(2‐chromonyl)alkanoic acids 2a , n = 3‐6 were also obtained from the cyclization of corresponding o ‐acetylphenyl ethyl alkanedioate 4 .