| Identification | Back Directory | [Name]
1,1-Dichloro-2,2,2-trimethyl-1-phenyldisilane | [CAS]
57519-88-7 | [Synonyms]
1,1-Dichloro-2,2,2-trimethyl-1-phenyldisilane
Disilane, 1,1-dichloro-2,2,2-trimethyl-1-phenyl- | [Molecular Formula]
C9H14Cl2Si2 | [MDL Number]
MFCD17013556 | [MOL File]
57519-88-7.mol | [Molecular Weight]
249.28 |
| Hazard Information | Back Directory | [Physical properties]
bp 50–60°C/0.5 mmHg. | [Uses]
In the presence
of palladium–phosphine catalysts such as tetrakis(triphenylphosphine)
palladium(0), the unsymmetrically substituted
disilane PhCl2SiSiMe3 reacts with α,β-unsaturated ketones in refluxing
benzene to give γ-(phenyldichlorosilyl) silyl enol ethers,
which can be converted into β-(phenyldiethoxysilyl) ketones
by treatment with ethanol and triethylamine (eq 1).Oxidation
of the phenyldiethoxysilyl group with hydrogen peroxide
in the presence of fluoride gives β-hydroxy ketones in high
yields. γ-(Phenyldimethylsilyl) lithium enolates, generated by
treatment of the γ-(phenyldichlorosilyl) silyl enol ethers with
methyllithium, undergo alkylation with alkyl halides to give β-
(phenyldimethylsilyl)-α-alkyl ketones with high anti selectivity
(eq 2). These β-(phenyldimethylsilyl) ketones are subjected to fluorodephenylation
followed by oxidation to give anti-β-hydroxy-
α-alkyl ketones. The 1,4-addition of the disilane is enantioselective
when catalyzed by PdCl2[(R)-BINAP], thereby providing
optically active anti-β-hydroxy-α-alkyl ketones with 66–92% ee
(Table 1). | [Preparation]
the disilane is prepared in 75% yield by
selective chlorodephenylation of 2,2,2-trimethyl-1,1,1-triphenyldisilane
with hydrogen chloride in the presence of a catalytic
amount of aluminum chloride in benzene. | [storage]
1,1-Dichloro-2,2,2-trimethyl-1-phenyldisilane reacts with air and water, and should be kept sealed to preclude decomposition. It is a potential acidic corrosive. It should be handled in a well ventilated hood.
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