Synthesis 2015; 47(23): 3783-3796
DOI: 10.1055/s-0035-1560463
paper
© Georg Thieme Verlag Stuttgart · New York

One-Pot, Highly Regioselective 1,3-Dipole Cycloaddition Promoted by Montmorillonite for the Synthesis of Spiro[indole-pyrrolizine], Spiro[indole-indolizine], and Spiro[indole-pyrrolidine] gem-Bisphosphonates

Guozhu Li
Key Laboratory of Tropical Medicinal Plant Chemistry of the Ministry of Education, College of Chemistry & Chemical Engineering, Hainan Normal University, Gui Linyang University Town, 2nd Road Xiaoji, 571158, P. R. of China   Email: wmsh@hainnu.edu.cn
,
Mingshu Wu*
Key Laboratory of Tropical Medicinal Plant Chemistry of the Ministry of Education, College of Chemistry & Chemical Engineering, Hainan Normal University, Gui Linyang University Town, 2nd Road Xiaoji, 571158, P. R. of China   Email: wmsh@hainnu.edu.cn
,
Fengjiao Liu
Key Laboratory of Tropical Medicinal Plant Chemistry of the Ministry of Education, College of Chemistry & Chemical Engineering, Hainan Normal University, Gui Linyang University Town, 2nd Road Xiaoji, 571158, P. R. of China   Email: wmsh@hainnu.edu.cn
,
Jie Jiang
Key Laboratory of Tropical Medicinal Plant Chemistry of the Ministry of Education, College of Chemistry & Chemical Engineering, Hainan Normal University, Gui Linyang University Town, 2nd Road Xiaoji, 571158, P. R. of China   Email: wmsh@hainnu.edu.cn
› Author Affiliations
Further Information

Publication History

Received: 21 June 2015

Accepted after revision: 20 July 2015

Publication Date:
31 August 2015 (online)


Abstract

Various spiro[indole-pyrrolizine], spiro[indole-indolizine], and spiro[indole-pyrrolidine] gem-bisphosphonates were prepared by multicomponent reactions between isatins, tetraethyl vinylidenebis(phosphonate), and amino acids in the presence of montmorillonite. The one-pot reactions proceeded by 1,3-dipole cycloadditions of azomethine ylides formed in a decarboxylative manner. The proposed mechanism is in line with experimental data that confirmed that the azomethine ylide is formed in a decarboxylative manner; this provides new insight into the underlying mechanisms of such cycloadditions. The method has many notable features, such as a broad substrate scope, high efficiency, and high regioselectivity.

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