Stereoselective synthesis of (E)-N, N-diethyl-3-(imidazo [1,2-a]pyrid-2-yl)-2-(phenylsulfonyl)propenamide

Abstract The title compound, gem -amidovinylsulfone 3 , was synthesized stereoselectively by aldolic condensation of N , N -diethylphenylsulfonylacetamide 1 on imidazo[1,2- a ]pyridine-2-carbaldehyde 2 adding Et 3 N at the end. The X-ray crystal structure of 3 [C 20 H 21 N 3 O 3 S: M r =383.5, monoclinic, P 2 1 , a =8.191(4) A, b =21.132(2) A, c =11.752(1) A, β =96.40(2)°, V =2022(1) A 3 , Z =4 (two molecules per asymmetric unit), D calc =1.260 g cm −3 , λ (Mo Kα)=0.71073 A, μ =0.184 mm −1 , F (000)=808, T=293(2) K , R =0.059 for 5105 observed reflections with I ≥2 σ ( I )] was determined, and confirmed the ( E ) configuration.