Trimethylsilyl

The trimethylsilyl ( TMS abbr. ) is a functional group in organic chemistry. The organosilicon compound made ​​up of three methyl groups bonded to a central silicon atom ( [- Si ( CH3 ) 3] ) which in turn is bonded to the remainder of the molecule. The group is characterized by their chemical inertness and its high molecular volume and finds, among other things as a protective group.

To introduce a TMS trimethylsilyl protecting group is usually used ( TMSCl ). In the preparation of silyl ethers ( [ -O-Si (CH3) 3 ] ) from alcohols of the alcohol is deprotonated and then nucleophilically attacks the silicon atom, whereby in the sense of an SN2 reaction, a chloride ion is released.

The inert tetramethylsilane also abbreviated to TMS trimethylsilyl is attached to a further methyl group. Tetramethylsilane as a reference substance found in NMR spectroscopy using.