Palladium-Catalyzed Reduction of N-(tert-Butoxycarbonyl)indoles by Polymethylhydrosiloxane [1]

Abstract

The palladium-catalyzed [10% Pd(OH)₂/C] reduction of N-(tert-butoxycarbonyl)indoles to the corresponding N-(tert-butoxy­carbonyl)indolines is described. Polymethylhydrosiloxane was used as reducing agent and the reaction proceeded smoothly at room temperature in short reaction times giving the products in good yields.

Key words

palladium catalysis - reduction - indoles - polymethyl­hydrosiloxane

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IICT Communication No. 070210.

References

• 2a Robinson B. Chem. Rev.  1969,  69:  785 
• 2b Gribble GW. In Comprehensive Organic Synthesis   Vol. 8:  Trost BM. Fleming I. Pergamon; Oxford: 1991.  p.612 
• 3a Kumar Y. Florvall L. Synth. Commun.  1983,  13:  489 
• 3b Gribble GW. Nutaitis CF. Leese RM. Heterocycles  1984,  22:  379 
• 3c Ketcha DM. Lieurance BA. Tetrahedron Lett.  1989,  30:  6833 
• 4 Kotsuki H. Ushio Y. Ochi M. Heterocycles  1987,  26:  1771 
• 5 Youn IK. Yon GH. Pak CS. Tetrahedron Lett.  1986,  27:  2409 
• 6a Lanzilotti AE. Littell R. Fanshawe WJ. McKenzie TC. Lovell FM. J. Org. Chem.  1979,  44:  4809 
• 6b Ward JS. Fuller RW. Merritt L. Snoddy HD. Paschal JW. Mason NR. Horng JS. J. Med. Chem.  1988,  31:  1512 
• 7a Okamoto Y. Osawa T. Kurasawa Y. Kinoshita T. Takagi K. J. Heterocycl. Chem.  1986,  23:  1383 
• 7b Chu CK. Suh J. Cutler HG. J. Heterocycl. Chem.  1986,  23:  1777 
• 7c Kikugawa Y. J. Chem. Res., Synop.  1977,  212 
• 7d Jones RJ. Cava MP. J. Chem. Soc., Chem. Commun.  1986,  826 
• 7e Berger JG. Synthesis  1974,  508 
• 8a Kuwano R. Sato K. Ito Y. Chem. Lett.  2000,  428 
• 8b Coulton S. Tetrahedron  1997,  53:  791 
• 8c Lunn G. J. Org. Chem.  1987,  52:  1043 
• 8d Shaw JE. Stapp PR. J. Heterocycl. Chem.  1987,  24:  1477 
• 8e Kikugawa Y. Kashimura M. Synthesis  1982,  785 
• 9a Ketcha DM. Homan DFJ. Lieurance BA. Gribble GW. J. Org. Chem.  1989,  54:  4350 
• 9b Ketcha DM. Gribble GW. J. Org. Chem.  1985,  50:  5451 
• 10a Rowlet AG. Chem. Ber.  1993,  29:  959 
• 10b Grundy C. Chem. Ber.  1997,  33:  33 
• 11 Lawrence NJ. Drew MD. Bushell SM. J. Chem. Soc., Perkin Trans. 1  1999,  3381 
• 12a Chandrasekhar S. Chandrashekar G. Vijeender K. Reddy MS. Tetrahedron Lett.  2006,  47:  3475 
• 12b Chandrasekhar S. Chandrashekar G. Babu BN. Vijeender K. Venkatram Reddy K. Tetrahedron Lett.  2004,  45:  5497 
• 12c Chandrasekhar S. Babu BN. Ahmed M. Reddy MV. Srihari P. Jagadeesh B. Prabhakar A. Synlett  2004,  1303 
• 12d Chandrasekhar S. Reddy CR. Babu BN. Tetrahedron Lett.  2003,  44:  2057 
• 12e Chandrasekhar S. Reddy CR. Babu BN. J. Org. Chem.  2002,  67:  9080 
• 13 For an exhaustive review on PMHS, see ref. 11, and also see: Senapati KK. Synlett  2005,  1960 
• 14 Boger DL. McKie JA. J. Org. Chem.  1995,  60:  1271 
• 15 Belsky I. Gertner D. Zilkha A. J. Org. Chem.  1968,  33:  1348 

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IICT Communication No. 070210.