Synfacts 2006(12): 1294-1294  
DOI: 10.1055/s-2006-955625
Polymer-Supported Synthesis
© Georg Thieme Verlag Stuttgart · New York

Sulfonic Acid Functionalized Silica Catalyst for the Boc Protection of Amines

Contributor(s): Yasuhiro Uozumi, Yoichi M. A. Yamada, Takayasu Arakawa
B. Das*, K. Venkateswarlu, M. Krishnaiah, H. Holla
Indian Institute of Chemical Technology, Hyderabad, India
Further Information

Publication History

Publication Date:
22 November 2006 (online)

Significance

A facile and versatile method for the chemoselective Boc protection of amines by using a sulfonic acid functionalized silica catalyst 1 was developed. Thus, the Boc protection of 1-phenylethylamine was carried out with catalyst 1 (1 mol%) and Boc2O (0.9 mol equiv) to give the Boc-protected amine in 99% yield. The catalyst 1 was reused without loss of catalytic activity [(97% (2nd use of 1); 96% (3rd use of 1), 94% (4th use of 1)]. The Boc protection of various amines by using catalyst 1 was also demonstrated (24 examples, 71-99% yield).