title: Tin powder-promoted one-pot synthesis of 3-spiro-fused or 3,3'-disubstituted 2-oxindoles.
abstract: A convenient and efficient method for the constructions of 3-spirooxindole derivatives or 3,3'-disubstituted oxindoles has been developed from one-pot reactions of isatins, hydrazides or aromatic amines, 2-(bromomethyl)acrylic ester and tin powder in the presence of a catalytic amount of Brønsted or Lewis acid. The method avoids the use of toxic stannanes and allows easy operation. It is also proved that hydrazides are more favorable for intramolecular cyclization than amines.
authors.affiliation: College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, China.
authors.forename: Juanjuan
authors.initials: J
authors.lastname: Wang
authors.affiliation: College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, China.
authors.forename: Danfeng
authors.initials: D
authors.lastname: Huang
authors.affiliation: College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, China.
authors.forename: Ke-Hu
authors.initials: KH
authors.lastname: Wang
authors.affiliation: College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, China.
authors.forename: Xiansha
authors.initials: X
authors.lastname: Peng
authors.affiliation: College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, China.
authors.forename: Yingpeng
authors.initials: Y
authors.lastname: Su
authors.affiliation: College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, China and State Key Laboratory of Applied Organic Chemistry, Lanzhou University, Lanzhou 730000, P. R. China. huyl@nwnu.edu.cn huangdf@nwnu.edu.cn.
authors.forename: Yulai
authors.initials: Y
authors.lastname: Hu
authors.affiliation: College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou, Gansu 730070, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Fu