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tert-Butyldimethylchlorosilane is used to protect hydroxyl group in organic synthesis. It finds application in the synthesis of prostaglandin. It is also used as an auxiliary material for hypolipaemics such as lovastatin and simvastatin. It plays an important role in the preparation of isoxazolines N-oxides from alpha-bromonitroalkanes. It acts as a versatile protecting reagent for amines, amides and alcohols.
Reagent for silylation of hydroxyl functions (see Appendix 4), giving silyl ethers more stable to aqueous hydrolysis e.g. during work-up, than TMS. Various conditions have been used for the introduction of the group:
Imidazole in DMF: J. Am. Chem. Soc., 94, 6190 (1972); Et3N - DMAP: Tetrahedron Lett., 99 (1979); Org. Synth. Coll., 9, 136 (1998); N-ethyldiisopropylamine: Tetrahedron Lett., 25, 227 (1984); 1,1,3,3-tetramethylguanidine: J. Org. Chem., 49, 4657 (1984); K2CO3 (phase-transfer): Synth. Commun., 11, 545 (1981); DBU - superior to imidazole for thiols, amines and carboxylic acids: Tetrahedron Lett., 26, 475 (1985).
Cleavage is generally effected with fluoride ion e.g. TBAF in an aprotic system: J. Am. Chem. Soc., 94, 6190 (1972), or KF with a phase-transfer catalyst: J. Am. Chem. Soc., 90, 4462, 4464 (1968); 96, 2250 (1974); J. Chem. Soc., Chem. Commun., 514 (1979).
Many other reagents have been used, including:
Acidic ion-exchange resin: Tetrahedron Lett., 21, 137 (1980); NBS in DMSO: Synthesis, 234 (1980); BF3 etherate: Synth. Commun., 9, 295 (1979); FeCl3 or SnCl2 in acetonitrile: Synth. Commun., 20, 757 (1990); K 10 clay in aqueous methanol: J. Org. Chem. 61, 9026 (1996); DMSO-water at 90o; many other groups unaffected: Tetrahedron Lett., 38, 495 (1997). See also Pyridinium p-toluenesulfonate, A15708, and Triethylamine trihydrofluoride, L14417.
Zhao, W.; Gnanou, Y.; Hadjichristidis, N. Organocatalysis by hydrogen-bonding: a new approach to controlled/living polymerization of alfa-amino acid N-carboxyanhydrides. Polym. Chem. 2015, 6 (34), 6193-6201.
Garcia, M.; Bequette, B. J.; Moyes, K. M. Hepatic metabolic response of Holstein cows in early and mid lactation is altered by nutrient supply and lipopolysaccharide in vitro. J. Dairy Sci. 2015, 98 (10), 7102-7114.
Dichiarazioni di rischio (UE): H228-H314-H318
Flammable solid. Causes severe skin burns and eye damage. Causes serious eye damage.
Dichiarazioni precauzionali: P210-P280-P305+P351+P338-P309-P310a
Keep away from heat/sparks/open flames/hot surfaces. - No smoking. Wear protective gloves/protective clothing/eye protection/face protection. IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing. IF exposed or if you feel unwell: