Author/Authors :
Krompiec، نويسنده , , Stanis?aw and Penczek، نويسنده , , Robert and Bujak، نويسنده , , Piotr and Kubik، نويسنده , , Ewelina and Malarz، نويسنده , , Joanna and Penkala، نويسنده , , Mateusz and Krompiec، نويسنده , , Micha? and Ku?nik، نويسنده , , Nikodem and Maciejewski، نويسنده , , Hieronim، نويسنده ,
Abstract :
Two new methods for the synthesis of orthoesters and compounds containing an orthoester moiety (dihydroisoxazoles) are presented. Mixed orthoesters of general formulas RC(OR1)(OR2)2 and RC(OR1)(OR2)(OR3) were prepared via addition of ROH (R = Bu or m-methylphenyl) to O-allyl acetals (acrolein acetals: diethyl or cyclic, i.e., 2-vinyl-1,3-dioxanes or dioxolanes). The catalytic systems for these reactions were generated from [RuCl2(PPh3)3] and Na2CO3; {[RuCl2(COD)]x} or {[OsCl2(1,5-COD)]x}, PPh3, and Na2CO3. Compounds containing an orthoester moiety (dihydroisoxazoles) were prepared via tandem isomerization of O-allyl acetals (to O-vinyl acetals) catalyzed by ruthenium complexes followed by cycloaddition to in situ-generated 2,6-dichlorophenylnitrile oxide.
