Activation reactions of 1,1-dialkoxoalkanes and unsaturated O-donors by titanium tetrafluoride

The reactivity of TiF4 with a variety of non cyclic 1,1-dialkoxoalkanes [CH2(OR)2, R = Me, Et, Me2C(OMe)2, MeCH(OEt)2, ClCH2CH(OEt)2, CH(OMe)3, PhCCCH(OEt)2], 1,3-dioxolane, N2CHCO2Et and 1,2-epoxybutane has been investigated. Activation, including fragmentation and/or rearrangement of the organic moiety, has been observed at room temperature in some cases; it generally occurs unselectively via C−O bond fission and the formation of new C−O, C−H and C−C bonds. Small differences in the structure of the organic substrate may determine significant differences in the reactivity with TiF4.

Activation of a series of 1,1-dialkoxoalkanes and unsaturated oxygen compounds by TiF4 occurs at room temperature via C−O bond fission and formation of new C−O, C−H and C−C bonds. Selective F-transfer has been observed with ethyldiazoacetate.Figure optionsDownload as PowerPoint slideHighlights
► The reactivity of TiF4 with 1,1-dialkoxoalkanes has been studied.
► Small differences in the organic compound determine differences in the products.
► C–O bond fission and formation of new bonds occurs.
► Fluorine transfer to ethyldiazoacetate has been observed yielding CH2FCO2Et.