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DOI: 10.1055/s-2006-926256
Facile Cleavage of Silyl Protecting Groups with Catalytic Amounts of FeCl3
Publication History
Publication Date:
10 March 2006 (online)
Abstract
A very mild and environmentally benign method for removal of silyl protecting groups using catalytic amounts of iron ion in MeOH is presented. The method is particularly effective for cleaving triethylsilyl (TES) protecting groups.
Key words
deprotection - hydrolysis - removal - cleavage - iron ion
- For earlier references, see:
-
1a
Green TW.Wuts PGM. Protective Groups in Organic Synthesis 3rd ed.: Wiley; New York: 1999. -
1b
Kocienski P. Protecting Groups 3rd ed.: Georg Thieme; Stuttgart: 2004. -
1c
Jarowicki K.Kocienski P. J. Chem. Soc., Perkin Trans. 1 2000, 2495 - For recent references, see for example:
-
2a Phosphomolybdic acid on SiO2:
Kishore GD.Baskaran S. J. Org. Chem. 2005, 70: 4520 -
2b Pd-C/MeOH:
Ikawa T.Hattori K.Sajiki H.Hirota K. Tetrahedron 2004, 60: 6901 -
2c Pd-C/H2:
Kim S.Jacob SM.Chang C.-T.Bellone S.Powell W.Rokach J. Tetrahedron Lett. 2004, 45: 1973 -
2d KOH/EtOH:
Wang Y.-G.Jiang Z.-Y. Chem. Lett. 2003, 32: 568 -
2e CeCl3·H2O/MeCN and LiOH/DMF:
Ankala S.Fenteany G. Tetrahedron Lett. 2002, 43: 4729 -
2f ZnBr2/H2O-CH2Cl2 (5 equiv):
Crouch RD.Polizzi JM.Cleiman RA.Yi J.Romany CA. Tetrahedron Lett. 2002, 43: 7151 -
2g NaIO4/THF:
Wang M.Li C.Yin D.Liang X.-T. Tetrahedron Lett. 2002, 43: 8727 -
2h IBX/DMSO:
Wu Y.-K.Huang J.-H.Shen X.Tang C.-J.Li L. Org. Lett. 2002, 4: 2141 -
2i CBr4/MeOH, hν:
Chen M.-Y.Lu K.-C.Lee AS.-Y.Lin C.-C. Tetrahedron Lett. 2002, 43: 2777 -
2j Pd-C/MeOH:
Rotulo-Sims D.Prunet J. Org. Lett. 2002, 4: 4701 -
2k CAN on SiO2:
Hwu JR.Jain ML.Tsai FY.Tsay S.-C.Balakumar A.Hakimelahi GH. J. Org. Chem. 2000, 65: 5077 -
2l Oxaone/MeOH-H2O:
Sabitha G.Syamala M.Yadav JS. Org. Lett. 1999, 1: 1701 -
2m Sc(OTf)3/H2O-MeCN:
Oriyama T.Kobayashi Y.Noda K. Synlett 1998, 1047 -
2n I2/MeOH:
Vaino A.Szarek WA. Chem. Commun. 1996, 2351 -
2o For a recent review, see:
Crouch RD. Tetrahedron 2004, 60: 5833
References and Notes
General Procedure for Cleavage of Silyl Protecting Groups.
A solution of the substrate (ca. 0.3 M) in MeOH containing the indicated amount of FeCl3 was stirred at the ambient temperature (ca. 23 °C). The progress of the reaction was monitored with TLC. When the cleavage of the silyl protecting groups was complete, the reaction mixture was filtered through a short pad of silica gel to remove the inorganic salt (eluting with EtOAc). The filtrate and effluent were combined and concentrated on a rotary evaporator and the residue was purified by column chromatography on silica gel to give the product.