A new four-centre reaction of alkanol–alkoxide negative ions. The reaction of [RO–⋯ HOR] with alkoxysilanes. An ion cyclotron resonance study

Abstract

Alkanol–alkoxide negative ions [R¹O ⋯ H ⋯ OR²]^– react with alkoxysilanes Me ₃SiOR³ to produce both [M+R¹O^–] and [M+R²O^–] ions of trigonal bipyramidal geometry. When R¹ < R ² and either R¹ or R² Pr, the four-centre reaction [R¹O ⋯ H ⋯ OR²]^–+ Me₃SiOR³→[R²O ⋯ H ⋯ OR³]^–+ Me₃SiOR¹ is observed. Addition of [R¹O ⋯ H ⋯ OR²]^– in the reverse direction is not detected. Analogous reactions do not occur between Me₃SiX and [R¹O ⋯ H ⋯ OR²]^– when X = F, NHR, NR₂,SiMe₃, alkyl, allyl, propargyl, benzyl, or aryl, but [R¹O ⋯ H ⋯ X]^– ions of small abundance are formed when X = HO, OCOMe, OCN, and SR. Cyclic ethers react with alkanol–alkoxide negative ions by reaction (i;n= 2–4). [graphic ommitted]