Butyl-l- trimethylsilyloxy cyclohexene

The reactivity pattern (1) of silyl enol ethers and ketene acetals is based largely on their synthetic equivalence to enolate anions. Recently, a different spectrum of behaviour has been revealed, particularly in those reactions that involve direct reaction without prior generation of the enolate anion. Indeed, the historic development of silyl enol ethers can be seen in three separate phases, involving 

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Enol silyl ethers react with aldehydes with a catalytic amount of TBAF to give the aldol silyl ethers in good yields. These reactions generally proceed under very mild conditions and within shorter periods of time than conventional strong acidic or basic conditions. The products from4-f-butyl-l-methyl-2-(trimethylsilyloxy) cyclohexene and benzaldehyde show very good axial selectivity and a little anti-syn selectivity (eq 20). The aldol condensation of ketones and aldehydes can be achieved in one pot when ethyl (trimethylsilyl)acetate is used as a silylation agent with TBAF (eq 21). 

HEXAHYDRO - 4a,5 - DIMETHYL - 2(3H) - NAPHTHALE-NONE and 2-TRIMETHYLSILYLOXY-1,3-BUTADIENE AS A REACTIVE DIENE DIETHYL trans -4-TRIMETHYL-SILYLOXY-4-CYCLOHEXENE-l,2-DICARBOXYLATE. Sulfur substitution also continues to be of high interest, and three preparations on sulfide synthesis are included BENZYL SULFIDE DIALKYL AND ALKYL ARYL SULFIDES NEOPENTYL PHENYL SULFIDE and UNSYMMETRICAL DIALKYL DISULFIDES sec-BUTYL ISOPROPYL DISULFIDE. 

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