Qin, Zemin; Ma, Renchao; Ying, Shenpeng; Li, Fanzhu; Ma, Yongmin published the artcile< Synthesis of Substituted Pyrimido[1,2-b]indazoles through (3+2+1) Cyclization of 3-Aminoindazoles, Ketones, and N,N-Dimethylaminoethanol as One-Carbon Synthon>, Electric Literature of 94-02-0, the main research area is pyrimidoindazole preparation; aminoindazole ketone dimethylaminoethanol three component cyclization.
The 2-mono- or 2,3-disubstituted pyrimido[1,2-b]indazoles I (R1 = Ph, thiophen-2-yl, naphth-2-yl, etc.; R2 = H, Me; R3 = H, 10-Br, 9-Br, 8-Br, etc.) are synthesized by a (3+2+1) three-component cyclization of 3-aminoindazoles II, ketones R1C(O)CH2R2 and N,N-dimethylaminoethanol as a methine source. The reaction demonstrates good tolerance of both aromatic and aliphatic ketones, as well as various substitution patterns in air.
Advanced Synthesis & Catalysis published new progress about Cyclization ((3+2+1)). 94-02-0 belongs to class esters-buliding-blocks, and the molecular formula is C11H12O3, Electric Literature of 94-02-0.
Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics