Synthesis 2008(2): 311-319  
DOI: 10.1055/s-2007-1000850
FEATUREARTICLE
© Georg Thieme Verlag Stuttgart · New York

Mild and General Method for the Synthesis of Sulfonamides

José Luis García Ruano*a, Alejandro Parraa, Francisco Yuste*b, Virginia M. Mastranzob
a Departamento de Química Orgánica, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
Fax: +34(914)973966; e-Mail: joseluis.garcia.ruano@uam.es;
b Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Cd. Universitaria, Coyoacán 04510, México D. F., Mexico
e-Mail: yustef@servidor.unam.mx;
Further Information

Publication History

Received 21 November 2007
Publication Date:
18 December 2007 (online)

Abstract

Reaction of methyl sulfinates with lithium amides followed by 3-chloroperoxybenzoic acid oxidation of the resulting sulfinamides provides primary, secondary, and tertiary alkane-, arene- and heteroarenesulfonamides in high yields. This constitutes a mild and facile experimental protocol that avoids the use of hazardous, unstable, or volatile reagents and does not affect the configurational stability of the amines

8

This reagent must be handled with care because it is a gas that can cause eye, skin, and respiratory irritation.

13

Compounds 1o and 1r were prepared by refluxing a 1:1 mixture of the corresponding thiol and Et3N in DMF for 10 h in an open flask: Garcia Ruano, J. L.; Parra, A.; Aleman, J. Synthesis, unpublished results.

15

Analogous results were obtained with EtOH.

16

Methyl benzenesulfinate is stable for several months at -20 °C.

18

The amount of the amine could be reduced to 1.2 equiv when ultrasonic irradiation was used, without affecting the sulfonamide yields.

20

Reaction of 2p with MCPBA is very fast, but none of the resulting compounds could be isolated by chromatography, even using very polar solvents. MCPBA oxidation in media sufficiently acidic to protonate the pyridine nitrogen, was also unsuccessful.

21

Higher amounts of MCPBA were required, reactions are sluggish and the overall yields were lower.

55

Configuration of the corresponding sulfinamides (major and minor) were not assigned.