2-(Триметилсилил)этанол

Химические свойства

CLEAR COLOURLESS LIQUID

Физические свойства

bp 50–52 °C/10 mmHg, 71–73 °C/35 mmHg; d 0.825 g cm?3.

Использование

2-(Trimethylsilyl)ethanol is a protecting reagent for carboxyl, phosphoryl, hydroxyl, and amino groups. It participates in the reactions of Phenol and Acid Protection, Alcohol Protection, Hemiacetal Protection, Amine Protection, Enol Ether Synthesis, Carbohydrate Chemistry etc.

Подготовка

Three methods of preparation have been reported: (a) from the treatment of ethyl bromoacetate with zinc followed by the reaction with chlorotrimethylsilane1 and subsequent reduction of the resultant ethyl trimethylsilylacetate with lithium aluminum hydride2,3 or borane¨Ctetrahydrofuran(eq 1); (b) from the hydroboration/oxidation or oxymercuration/demercuration of vinyltrimethylsilane (eq 2); and (c)most conveniently, by the reaction of the Grignard reagent formed from (chloromethyl)trimethylsilane with paraformaldehyde (eq 3).

Методы очистки

If the NMR spectrum is not clean, then dissolve the alcohol in Et2O, wash it with aqueous NH4Cl solution, dry (Na2SO4), evaporate and distil it. The 3,4-dinitrobenzoyl derivative has m 66o (from EtOH). [NMR: Speier et al. J Am Chem Soc 79 974 1957, Z Naturforsch 14b 137 1959, Beilstein 4 IV 3951.]