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        Synthesis  2008(19): 3126-3130  
DOI: 10.1055/s-2008-1067272
   DOI: 10.1055/s-2008-1067272
PAPER
© Georg Thieme Verlag
      Stuttgart ˙ New York1,1,1,3,3,3-Hexafluoroisopropanol: A Recyclable Organocatalyst for N-Boc Protection of Amines
Weitere Informationen
            
               
                  
                        
                              Received
                              16 May 2008 
                      
Publikationsdatum:
05. September 2008 (online)
            
         
      
   Publikationsverlauf
Publikationsdatum:
05. September 2008 (online)

Abstract
A simple and efficient protocol for the chemoselective mono-N-Boc protection of various structurally diverse amines with di-tert-butyl dicarbonate using 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) as solvent and catalyst is described. The catalyst can be readily separated from the reaction products and recovered for direct reuse. No competitive side reactions such as formation of isocyanate, urea, and N,N-di-Boc were observed. α-Amino alcohols afforded the N-Boc derivatives without oxazolidinone formation.
Key words
amines - Boc anhydride - chemoselectivity - HFIP - organocatalyst - hydrogen bonding
- 1a 
             
            Wuensch E. In Houben-Weyl, Methods of Organic Chemistry 4th ed.; Vol. 15/1:Mueller E.Bayer O.Meerwein H.Ziegler K. Thieme; Stuttgart: 1974. p.46Reference Ris Wihthout Link
- 1b 
             
            Xiuo X.Ngu K.Choa C.Patel DV. J. Org. Chem. 1997, 62: 6968Reference Ris Wihthout Link
- 1c 
             
            Kociensky PJ. Protecting Groups Thieme; Stuttgart: 2000.Reference Ris Wihthout Link
- 1d 
             
            Greene TW.Wuts PGM. Protective Group in Organic Synthesis, 3rd ed. Wiley; New York: 1999.Reference Ris Wihthout Link
- 2 
             
            Merrifield RB. J. Am. Chem. Soc. 1964, 86: 304
- 3 
             
            Basel Y.Hassner A. J. Org. Chem. 2000, 65: 6368
- 4a Aqueous
            NaOH:  
            Lutz C.Lutz V.Knochel P. Tetrahedron 1998, 54: 6385Reference Ris Wihthout Link
- 4b K2CO3-Bu4NI
            in DMF:  
            Handy ST.Sabatini JJ.Zhang Y.Vulfora I. Tetrahedron Lett. 2004, 45: 5057Reference Ris Wihthout Link
- 4c Me4NOH˙5H2O
            in MeCN:  
            Khalil EM.Subasinghe NL.Johnson RL. Tetrahedron Lett. 1996, 37: 3441Reference Ris Wihthout Link
- 4d NaHCO3 in MeOH under
            sonication:  
            Eunhorn J.Einhorn C.Luche J.-L. Synlett 1991, 37Reference Ris Wihthout Link
- 4e NaHMDS in THF:  
            Kelly TA.McNeil DW. Tetrahedron Lett. 1994, 35: 9003Reference Ris Wihthout Link
- 5 
             
            Knoelker H.-J.Braxmeier T. Tetrahedron Lett. 1996, 37: 5861
- 6 
             
            Darnbrough S.Mervic M.Condon SM.Burns CJ. Synth. Commun. 2001, 31: 3273
- 7 
             
            Heydari A.Kazem Shiroodi R.Hamadi H.Esfandyari M.Pourayoubi M. Tetrahedron Lett. 2007, 48: 5865
- 8 
             
            Upadhyaya DJ.Barge A.Stefania R.Cravotto G. Tetrahedron Lett. 2007, 48: 8318
- 9 
             
            Bartoli G.Bosco M.Locatelli M.Marcantoni E.Massaccesi M.Melchiorr P.Sambri L. Synlett 2004, 1794
- 10 
             
            Sharma GVS.Reddy JJ.Lakshmi PS.Krishna PR. Tetrahedron Lett. 2002, 45: 6963
- 11 
             
            Heydari A.Hosseini SE. Adv. Synth. Catal. 2005, 347: 1929
- 12 
             
            Chankeshwara SV.Chakraborti AK. Tetrahedron Lett. 2006, 47: 1087
- 13 
             
            Chankeshwara SV.Chakraborti AK. J. Mol. Catal. A: Chem. 2006, 253: 198
- 14 
             
            Das B.Verkateswarlu K.Krishnaiah M.Holla H. Tetrahedron Lett. 2006, 47: 7551
- 15 
             
            Varala R.Nuvula S.Adapa SR. J. Org. Chem. 2006, 71: 8283
- 16 
             
            Chankeshwara SV.Chakraborti AK. Synthesis 2006, 2784
- 17 
             
            Kobayashi S.Araki M.Yasuda M. Tetrahedron Lett. 1995, 36: 5773
- 18 
             
            Klement I.Luetjens H.Knochel P. Angew. Chem., Int. Ed. Engl. 1997, 36: 1454
- 19 
             
            Bégué JP.Bonnet-Delpon D.Crousse B. Synlett 2004, 18
- 20 
             
            Povey JF.Smales CM.Hassard SJ.Howard MJ. J. Struct. Biol. 2007, 157: 329
- 21a 
             
            Hudlicky M. Chemistry of Organic Fluorine Compounds Ellis-Horwood; New York: 1992. , 2nd ed.Reference Ris Wihthout Link
- 21b 
             
            Organic
               Fluorine Chemistry. Principles and Applications
              
             
            Banks RE.Smart BE.Tatlow JC. Plenum; New York: 1994.Reference Ris Wihthout Link
- 22 
             
            Shuklov IA.Dubrovina NV.Boerner A. Synthesis 2007, 2925
- 23 
             
            Bartoli G.Bosco M.Locatelli M.Marcantoni E.Massaccesi M.Melchiorre P.Sambri L. Synlett 2004, 1794
 
    