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Synlett 2004(4): 675-678  
DOI: 10.1055/s-2004-817786
LETTER
© Georg Thieme Verlag Stuttgart · New York

Catalytic Polymer-Supported Potassium Thiophenolate in Methanol as a Method for the Removal of Ester, Amide, and Thioacetate Protecting Groups

Rachel N. MacCossa, Dara J. Henrya, Christopher T. Brainb, Steven V. Ley*a
a Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK
e-Mail: svl1000@cam.ac.uk;
b Novartis Institute for Medical Sciences, 5 Gower Place, London, WC1E 6BS, UK
Further Information

Publication History

Received 22 November 2003
Publication Date:
17 February 2004 (online)

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Abstract

Polymer-supported potassium thiophenolate to remove ester, activated amide, and thioacetate protecting groups catalytically in the presence of methanol is reported.

Key words

polymer-supported - thiophenolate - deprotection

    References

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2

Argonaut Technologies Catalog 2000, p. 53.

5

General Procedure: Protected compound (1.0 equiv) was dissolved in MeOH/THF (1:1) in a sealed vial and stirred with thiophenolate resin 1 (1.45 mmol/g, 0.2 equiv). The reaction was heated as described herein. When reaction was complete, the resin was removed by filtration and washed with THF. The combined washings were dried in vacuo. If starting material remained, the product was isolated by standard column chromatography.

6

Thiophenolate Resin: Polymer-supported thiophenol was shaken at r.t. under argon with potassium trimethylsilanolate in THF. After 2 d, the resin was rinsed with THF and dried in vacuo (1.45 mmol/g).

7

All compounds gave satisfactory spectroscopic data identical to those reported in the literature.

9

Resin was filtered, washed with CH2Cl2 three times, and dried in vacuo before reusing.