of substrate employed this is because the nahco 3 disproportionates under typical reaction conditions to give na 2 co 3 and h 2 o and co 2 thus up to one half of the reactant nahco 3 charged to the reaction may become unavailable for the desired oxidation reaction when the alkenyl halide v or alkynyl halide iii starting material is a chloride x u2550 cl sodium iodide nai may additionally be added to the reaction mixture addition of nai in any suitable amount preferably from about 1 to about 10 mol based on substrate serves to enhance the rate of the oxidation reaction when solvent is employed any suitable ratio of solvent and substrate alkenyl halide v or alkynyl halide iii can be used generally a 3 1 to about 1 3 solvent to substrate mix is employed reaction is preferably although not necessarily carried out at atmospheric pressure under an inert atmosphere n 2 ar or the like any suitable temperature and pressure may be employed temperatures employed are preferably about 90 u00b0 150 u00b0 c with 105 u00b0 to about 130 u00b0 c most preferred any reaction time is suitable although generally reaction times of 30 minutes to about 8 hours are employed with about 1 3 hours preferred any.