Process for the preparation of novel stabilized phosphorus ylides

A process for the preparation of compounds of formula (1), which comprises the steps of

• (a) reacting 2-formyl- or 2-oxoalkylidenetriphenylphosphorane with a chlorinating agent in a stoichiometric ratio of from about 1:1.5 to 1:2, at a temperature within the range from about 60.degree. to 150.degree. C., with a reaction time in the range from about 30 to 90 minutes to give compounds of formula (2)
• Ph.sub.3 P.sup.+ --CH.dbd.C(R)--Cl X (2)
• wherein X is Cl, Br or POCl.sub.2 ;
• and
• (b) reacting the compounds of formula (2) with nucleophiles (Nu) at a ratio of (Nu) to compounds of formula (2) of from about 1:1 to 1:2 at a reaction time in the range of from about 30 to 80 minutes and at a temperature in the range from about 20.degree. to 80.degree. C. to give compounds of formula (1)
• Ph.sub.3 P.dbd.CH--C(R).dbd.Nu (1)
• wherein R is hydrogen, C.sub.1 -C.sub.5 -alkyl, a C.sub.1 -C.sub.3 -fluoroalkyl or perfluoroalkyl radical, an unfluorinated or fluorinated C.sub.6 -C.sub.14 -aryl radical or OCH.sub.3, and
• Nu is S, Se, C(CN).sub.2, NH, PhN, PhNHN, CH.sub.3 COCCOCH.sub.3, CH.sub.3 OOCCCOOCH.sub.3 or a radical of the formulae (a), (b), (c), (d) or (e) ##STR10## wherein Z is C(CH.sub.3).sub.2, S or N(CH.sub.3) and n=1 or 2.