Indium(III) Halides as New and Highly Efficient Catalysts for N-tert-Butoxycarbonylation of Amines

Abstract

Indium(III) bromide and chloride efficiently catalysed the N-tert-butoxycarbonylation of amines with (Boc)₂O at room temperature and under solvent-free conditions. Various aromatic, heteroaromatic and aliphatic amines were converted to N-tert-butylcarbamates in excellent yields in short times. Chiral amines, esters of α-amino acids and β-amino alcohols afforded optically pure N-t-Boc derivatives in high yields. The reactions were chemoselective and no competitive side reactions such as isocyanate, urea, and N,N-di-t-Boc formation were observed. Chemoselective conversion to N-tert-butylcarbamates took place with amino alcohols without any formation of oxazolidinones.

Key words

indium(III) halides - N-tert-butylcarbamates - amines - chiral α-amino acid esters - di-tert-butyl dicarbonate - chemoselectivity - solvent-free - room temperature

References

• 1a Greene TW. Wuts PGM. Protecting Groups in Organic Synthesis   3rd ed.:  Wiley; New York: 1999. 
• 1b Theodoridis G. Tetrahedron  2000,  56:  2339 
• 1c Sartori G. Ballini R. Bigi F. Bosica G. Maggi R. Righi P. Chem. Rev.  2004,  104:  199 
• 2a Chakraborti AK. Gulhane R. Tetrahedron Lett.  2003,  44:  3521 
• 2b Chakraborti AK. Gulhane R. Chem. Commun.  2003,  1896 
• 2c Chakraborti AK. Gulhane R. Tetrahedron Lett.  2003,  44:  6749 
• 2d Chakraborti AK. Sharma L. Gulhane R. . Tetrahedron  2003,  59:  7661 
• 2e Chakraborti AK. Gulhane R. . Synlett  2003,  1805 
• 2f Chakraborti AK. Gulhane R. . Synthesis  2004,  111 
• 2g Chakraborti AK. Gulhane R. Synlett  2004,  627 
• 3 Dilbeck GA. Field L. Gallo AA. Gargiulo RJ. J. Org. Chem.  1978,  43:  4593 
• 4 Agami C. Couty F. Tetrahedron  2002,  58:  2701 
• 5 Lutz C. Lutz V. Knochel P. Tetrahedron  1998,  54:  6385 
• 6a Grehn L. Ragnarsson U. Angew. Chem., Int. Ed. Engl.  1984,  23:  296 
• 6b Grehn L. Ragnarsson U. Angew. Chem., Int. Ed. Engl.  1985,  24:  510 
• 6c Burk MJ. Allen JG. J. Org. Chem.  1997,  62:  7054 
• 6d Basel Y. Hassner A. J. Org. Chem.  2000,  65:  6368 
• 7a NaHCO₃ in MeOH under sonication: Einhorn J. Einhorn C. Luche J.-L. Synlett  1991,  37 
• 7b Me₄NOH·5H₂O in MeCN: Khalil EM. Subasinghe NL. Johnson RL. Tetrahedron Lett.  1996,  37:  3441 
• 7c NaHMDS in THF: Kelly TA. McNeil DW. Tetrahedron Lett.  1994,  35:  9003 
• 7d Aqueous NaOH: Lutz C. Lutz V. Knochel P. Tetrahedron  1998,  54:  6385 
• 7e K₂CO₃-Bu₄NI in DMF: Handy ST. Sabatini JJ. Zhang Y. Vulfova I. Tetrahedron Lett.  2004,  45:  5057 
• 8 Guibé-Jampel E. Wakselman M. J. Chem. Soc., Chem. Commun.  1971,  267 
• 9 Guibé-Jampel E. Wakselman M. Synthesis  1977,  772 
• 10 Itoh M. Hagiwara D. Kamiya T. Tetrahedron Lett.  1975,  4393 
• 11 Kim S. Lee JI. Chem. Lett.  1984,  237 
• 12 Barcelo G. Senet J.-P. Sennyey G. Synthesis  1986,  627 
• 13a Sweet DV. Registry of Toxic Effects of Chemical Substances 1985-86   US Govt. Printing Office; Washington DC: 1988.  p.3336 
• 13b Sweet DV. Registry of Toxic Effects of Chemical Substances 1985-86   US Govt. Printing Office; Washington DC: 1988.  p.4049 
• 14a Knölker H.-J. Braxmeier T. Tetrahedron Lett.  1996,  37:  5861 
• 14b Knölker H.-J. Braxmeier T. Schlechtingen G. Angew. Chem., Int. Ed. Engl.  1995,  34:  2497 
• 15 Darnbrough S. Mervic M. Condon SM. Burns CJ. Synth. Commun.  2001,  31:  3273 
• 16 Pandey RK. Dagade SP. Upadhyay RK. Dongare MK. Kumar P. ARKIVOC  2002,  vii:  28 ; www. arkat-usa.org
• 17 Bartoli G. Bosco M. Locatelli M. Marcantoni E. Massaccesi M. Melchiorre P. Sambri L. Synlett  2004,  1794 
• 18 Sharma GVS. Reddy JJ. Lakshmi PS. Krishna PR. Tetrahedron Lett.  2004,  45:  6963 
• 19 Heydari A. Hosseini SE. Adv. Synth. Catal.  2005,  347:  1129 
• 20a Schumacher JC. Perchlorates - Their Properties, Manufacture and Uses, ACS Monograph Series   Reinhold; New York: 1960. 
• 20b Long J. Chem. Health Safety  2002,  9:  12 
• 21 Chankeshwara SV. Chakraborti AK. Tetrahedron Lett.  2006,  47:  1087 
• 22a Clark JH. Green Chem.  1999,  1 
• 22b Tundo P. Anastas P. Black DS. Breen J. Collins T. Memoli S. Miyamoto J. Polyakoff M. Tumas W. Pure Appl. Chem.  2000,  72:  1207 
• 23a Nair V. Ros S. Jayan CN. Pillai BS. Tetrahedron  2004,  60:  1959 
• 23b Frost CG. Hartley JP. Mini-Rev. Org. Chem.  2004,  1:  1 
• 23c Ranu BC. Eur. J. Org. Chem.  2000,  2347 
• 23d Chauhan KK. Frost CG. J. Chem. Soc., Perkin Trans. 1  2000,  3015 
• 24a Dondoni A. Perrone D. Semola T. Synthesis  1995,  181 
• 24b Green R. Taylor PJM. Bull SD. James TD. Mahon MF. Merritt AT. Tetrahedron: Asymmetry  2003,  14:  2619 
• 24c

  Aldrich Handbook of Fine Chemicals and Laboratory Equipments, India 2003-2004; 336

• 24d

  Aldrich Advancing Science, India 2005-2006; 514

• 24e

  Donboo Amino Acid Co. Ltd., http://www.donboo.com/english/detail.asp?id = 221.

• 25 Lebel H. Leogane O. Org. Lett.  2005,  7:  4107 
• 26a Garrett RL. In Designing Safer Chemicals: American Chemical Society Symposium Series 640   Garrett RL. De Vito SC. American Chemical Society; Washington DC: 1996.  Chap. 1.
• 26b Cave GWV. Raston CL. Scott JL. Chem. Commun.  2001,  2159 
• 27 Tundo P. Anastas P. Black DS. Breen J. Collins T. Memoli S. Miyamoto J. Polyakoff M. Tumas W. Pure Appl. Chem.  2000,  72:  1207