Etudes infrarouge et NMR d'aryl-2 dihydro-1,2 (4H) thiéno[2,3-c]benzo[e]pyrannones-4

Crystal structure of the 1,2-dihydro-4H-thieno [2,3-c] benzo[e]pyran-4-one, C11H8O2S

The title compound C11H8O2S (I) crystallizes in space group C2/c: a = 11.468(4) Å, b = 8.767(1) Å, c = 19.249(6) Å, β = 107.20(2)°; V = 1848.6(1.4) Å3; Z = 8, Dx = 1466 kg m−3; Cu Kα = 1.542 Å, μ = 27 cm−1; F(000) = 848; T = 293(1) K; Conventional R = 0.10 = Rw for 1594 unique reflections.

(I) is almost flat and exhibits no pharmacological activity, whereas is non-planar phenyl derivative (II) has a strong antalgic action.

Combined directed ortho and remote metalation-Suzuki cross-coupling strategies. Efficient synthesis of heteroaryl-fused benzopyranones from biaryl O-carbamates

A concise synthesis of heteroaryl dibenzopyranones 9a,b, 10a,b, 11a-c, and 12a-c has been achieved by the LDA-induced migration of heterobiaryl O-carbamates 18, 21, 25, and 30 which, in turn, were prepared in good yield using a combined directed ortho lithiation (DoM)-transition-metal-catalyzed Suzuki cross-coupling strategy. An efficient and general route to a wide variety of heterocycles including coumestans 19a,c and the previously unknown isothiocoumestan ring system 22b has been thereby achieved.