New fluoride ion-catalyzed reaction of -alkylacetylenes with silyl enol ethers. An efficient route to -alkyl-substituted propargylic alcohols and α-hydroxy ketones
Treatment of -alkylacetylenes, generated from 1--1- alkenephosphonates, with silyl enol ethers in the presence of a catalytic amount of tetrabutylammonium fluoride gives good yields of -alkyl-substituted propargyl alcohols or 4-(1--alkylidene)-1,3-dioxolane derivatives, the latter being converted to tie corresponding α-hydroxy ketones.
Diethyl (Z)-1H-F-1-alkene-1-phosphonates were synthesized in good yields by the treatment of diethyl (Z)-1-[(diethoxyphosphinyl) oxy]-F-1-alkene-1-phosphonates, prepared from F- alkanoic acid chlorides and triethyl phosphite, with butylcopper (I) reagent in tetrahydrofuran-tetramethylethylenediamine at −78 °C.
New organocuprate-induced reduction of the enol phosphate moiety in 1-[(diethoxyphosphinyl)oxy]-F-1-alkene-1-phosphonates: an efficient synthesis of (Z)-1-hydro-F-1-alkene-1-phosphonates