Wang, Lei; Li, Sun; Chauhan, Pankaj; Hack, Daniel; Philipps, Arne R.; Puttreddy, Rakesh; Rissanen, Kari; Raabe, Gerhard; Enders, Dieter published the artcile< Asymmetric, Three-Component, One-Pot Synthesis of Spiropyrazolones and 2,5-Chromenediones from Aldol Condensation/NHC-Catalyzed Annulation Reactions>, Computed Properties of 3893-18-3, the main research area is pyrazolone enal NHC chiral aldol condensation annulation catalyst; spiropyrazolone stereoselective preparation; diketone cyclic enal NHC chiral aldol condensation annulation catalyst; chromenedione stereoselective preparation; N-heterocyclic carbene; asymmetric synthesis; chromenedione; multicomponent reaction; spiropyrazolone.
A novel one-pot, three-component diastereo- and enantioselective synthesis of spiropyrazolones has been developed involving the aldol condensation of an enal to generate α,β-unsaturated pyrazolones, which react with a second equivalent of enal through an N-heterocyclic carbene (NHC)-catalyzed [3+2] annulation. The desired spirocyclopentane pyrazolones I (R = Ph, 4-MeOC6H4, 2-MeOC6H4, 4-ClC6H4, 4-BrC6H4, 2-furanyl, 3-thienyl, etc.; R1 = t-Bu, Et, 4-MeOC6H4, 2-naphthyl; R2 = Ph, 4-MeOC6H4, 4-BrC6H4, Bn, t-Bu, etc.) are obtained in moderate to good yields and good to excellent stereoselectivities. Alternatively, starting from cyclic 1,3-diketones, 2,5-chromenediones II (R = Ph, 4-MeOC6H4, 4-MeC6H4, 4-ClC6H4, 2-MeOC6H4, etc.; R1= R2= Me, H; R1= H, R2= Ph) are available through [2+4] annulation.
Chemistry – A European Journal published new progress about Aldol condensation. 3893-18-3 belongs to class bromides-buliding-blocks, and the molecular formula is C9H7BrO, Computed Properties of 3893-18-3.
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary