?Acute toxicity
IV- mouse LD50: 56 mg/kg
Description
Triphenylsilyl chloride is a white to off-white crystal or powder with acrid ordor of hydrogen chloride, used for synthesis of pharmaceutical intermediates.
Physical properties
mp 92–94°C; bp 240–243°C/35 mmHg.
Uses
A wide variety of Grignard reagents and organolithium complexes
participate in reactions with Ph3SiCl to afford organosilanes.
Thus the reaction of allylmagnesium chloride with Ph3SiCl gives the allylsilane in high yield (eq 3).However, when hydrosilyl
Grignard reagents are employed, reduction to the silane
occurs (eq 4).Azaallyl anion6 and diazolithium salts can each
be silylated to give the anticipated silane adducts (eqs 5 and 6).
Similarly, arylsilanes8 and alkynylsilanes are produced upon
silylation of the appropriate metalated13 carbanions with Ph3SiCl
(eqs 7–11).
Uses
Chlorotriphenylsilane is used as a silylating agent. It is also used as a pharmaceutical intermediate.
Purification Methods
Likely impurities are tetraphenylsilane, small amounts of hexaphenyldisiloxane and traces of triphenylsilanol. Purify it by distillation at 2mm, then crystallise it from EtOH-free CHCl3, and from pet ether (b 30-60o) or hexane by cooling in a Dry-ice/acetone bath. [Allen & Modena J Chem Soc 3671 1957, Curran et al. J Am Chem Soc 72 4471 1950, Speier & Zimmerman J Am Chem Soc 77 6395 1955, Thomas & Rochow J Am Chem Soc 79 1843 1957, Beilstein 16 IV 1484.]
