Desulfurization of Thioamides into Amides with H₂O₂/ZrCl₄ Reagent System

Abstract

The hydrogen peroxide/zirconium(IV) chloride reagent system has been used as a new and efficient reagent for the deprotection/desulfurization of thioamides to amides. This system is reasonably general and can be applied to the conversion of several thioamides to the corresponding amides. The salient features of this protocol are short reaction times, good chemoselectivity, cleaner reaction profiles, and simple workup that precludes the use of toxic solvents.

deprotection - thioamides - amides - desulfurization - hydrogen peroxide

References

<A NAME="RZ19708SS-1">1</A> Shaabani A. Soleimani E. Rezayan AH. Tetrahedron Lett.  2007,  48:  6137 

<A NAME="RZ19708SS-2">2</A> Mohammadpoor-Baltork I. Khodaei MM. Nikoofar K. Tetrahedron Lett.  2003,  44:  591 

<A NAME="RZ19708SS-3">3</A> Mohammadpoor-Baltork I. Memarian HR. Hajipour AR. Bahrami K. Bull. Korean Chem. Soc.  2003,  24:  1002 

<A NAME="RZ19708SS-4">4</A> Mohammadpoor-Baltork I. Memarian HR. Bahrami K. Monatsh. Chem.  2002,  133:  189 

<A NAME="RZ19708SS-5">5</A> Movassagh B. Lakouraj MM. Ghodrati K. Synth. Commun.  2000,  30:  2353 

<A NAME="RZ19708SS-6">6</A> Masuda R. Hojo M. Ichi T. Sasano S. Kobayashi T. Kuroda C. Tetrahedron Lett.  1991,  32:  1195 

<A NAME="RZ19708SS-7A">7a</A> Kim HJ. Kim YH. Synthesis  1986,  970 

<A NAME="RZ19708SS-7B">7b</A> Rahman A.-U. Basha A. Waheed N. Tetrahedron Lett.  1976,  17:  219 

<A NAME="RZ19708SS-7C">7c</A> Tani J. Oine T. Inoue I. Synthesis  1975,  714 

<A NAME="RZ19708SS-8">8</A> Kochharl KS. Cottrell DA. Pinnick HW. Tetrahedron Lett.  1983,  24:  1323 

<A NAME="RZ19708SS-9">9</A> Mukherji P. Indian J. Chem., Sect. B: Org. Chem. Incl. Med. Chem.  1977,  15:  202 

<A NAME="RZ19708SS-10">10</A> Mikolajzyk M. Luczak J. Synthesis  1974,  491 

<A NAME="RZ19708SS-11">11</A> Mikolajzyk M. Luczak J. Synthesis  1975,  114 

<A NAME="RZ19708SS-12">12</A> Olah CA. Arvanaghi M. Ohannesian L. Surya PGK. Synthesis  1984,  785 

<A NAME="RZ19708SS-13">13</A> Mikolajzyk M. Luczak J. J. Org. Chem.  1978,  43:  2132 

<A NAME="RZ19708SS-14">14</A> Singh H. Singh P. Malhotra N. J. Chem. Soc., Perkin Trans. 1  1981,  2647 

<A NAME="RZ19708SS-15">15</A> Boudet R. Bull. Soc. Chim. Fr.  1951,  377 

<A NAME="RZ19708SS-16A">16a</A> Sato K. Aoki M. Noyori R. Science  1998,  281:  1646 

<A NAME="RZ19708SS-16B">16b</A> Brink GT. Arends IWC. Sheldon RA. Science  2000,  287:  1636 

<A NAME="RZ19708SS-17">17</A> Bahrami K. Tetrahedron Lett.  2006,  47:  2009 

<A NAME="RZ19708SS-18">18</A> Bahrami K. Khodaei MM. Kavianinia I. Synthesis  2007,  547 

<A NAME="RZ19708SS-19A">19a</A> Khodaei MM. Bahrami K. Karimi A. Synthesis  2008,  1682 

<A NAME="RZ19708SS-19B">19b</A> Bahrami K. Khodaei MM. Karimi A. Synthesis  2008,  2543