prov:value
| - erified later in the presence of a base, for example sodium hydride, potassium tert-butylate, alkali metal hydroxide or alkali metal carbonate, in an inert solvent at -20??? to 100??? C., using compounds of the formula R2 --Hal, and where R6 is CH3, COXR or CN, R is C1 -C4 alkyl and R2, X1, X2 and X3 have the meanings given under formula I; and
|