Synthesis 2016; 48(09): 1371-1380
DOI: 10.1055/s-0035-1560422
paper
© Georg Thieme Verlag Stuttgart · New York

One-Pot Synthesis of Spirotetrahydrooxino[3,4-c]pyridines and Spirotetrahydrofuro[3,2-b]pyridin-2-ones via Lactonization from Activated Pyridyldihydroozaxoles and Bis(trimethylsilyl)ketene Acetals

Authors

  • Omar Gómez-García*

    a   Instituto de Química-UNAM, Circuito Exterior, Ciudad Universitaria, Coyoacán, C.P. 04510, México D.F., México   eMail: cecilio@unam.mx   eMail: jogomez@encb.ipn.mx
  • Elizabeth Gómez

    a   Instituto de Química-UNAM, Circuito Exterior, Ciudad Universitaria, Coyoacán, C.P. 04510, México D.F., México   eMail: cecilio@unam.mx   eMail: jogomez@encb.ipn.mx
  • Rubén A. Toscano

    a   Instituto de Química-UNAM, Circuito Exterior, Ciudad Universitaria, Coyoacán, C.P. 04510, México D.F., México   eMail: cecilio@unam.mx   eMail: jogomez@encb.ipn.mx
  • Héctor Salgado-Zamora

    b   Departamento Química Orgánica, Escuela Nacional de Ciencias Biológicas-IPN, Prolongación de Carpio y Plan de Ayala S/N, Colonia Santo Tomás, 11340 México, D.F., México
  • Cecilio Álvarez-Toledano*

    a   Instituto de Química-UNAM, Circuito Exterior, Ciudad Universitaria, Coyoacán, C.P. 04510, México D.F., México   eMail: cecilio@unam.mx   eMail: jogomez@encb.ipn.mx
Weitere Informationen

Publikationsverlauf

Received: 30. November 2015

Accepted after revision: 05. Februar 2016

Publikationsdatum:
01. März 2016 (online)


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Abstract

5-Methyl-2-(pyridin-3-yl)-4,5-dihydrooxazole and 5-methyl-2-(pyridin-4-yl)-4,5-dihydrooxazole activated by triflic anhydride underwent lactonization with bis(trimethylsilyl)ketene acetals to provide tetrahydrooxino[3,4-c]pyridines and tetrahydrofuro[3,2-b]pyridin-2-ones. Formation of the product was controlled by the position of the pyridyl substituent at C-3 and C-4 of the pyridyldihydrooxazole. On the other hand, 1-(trifluoromethylsulfonamido)propan-2-yl picolinate was obtained under the same conditions from 5-methyl-2-(pyridin-2-yl)-4,5-dihydrooxazole.

Supporting Information