Synthesis of a particular class of silicon-tethered dinucleophiles : Several propargyloxydimethylsilyl enol ethers

Abstract The propargyloxydimethylsilyl enol ethers derived from propanone, 2‐butanone, 3,3‐dimethyl‐2‐butanone, 3‐pentanone, 4‐methyl‐2‐pentanone, 2‐heptanone, 4‐heptanone, 2,6‐dimethyl‐4‐heptanone, cyclopentanone, cyclohexanone, cycloheptanone, benzophenone, and propiophenone have been synthesized by two methods: The thermodynamic method is conducted by heating the propargyloxysilyl chloride, triethylamine, and the corresponding ketone in acetonitrile at 40–50°C for less than an hour in the presence of an equimolar amount of sodium iodide; the mixture is maintained at that temperature for an hour. The yields were in the range of 50–95%. In method two (kinetic controlled), lithium diisopropylamide (LDA) was used as a base to abstract the acidic hydrogen, and then the resulted enolate was quenched with silyl chloride, with lower yields than the previous method. NMR, IR, and elemental analysis were used to characterize the products. Some reactions of these compounds have been investigated.