| 摘要 |
The present invention relates to a process for the preparation of compounds of formula (I) wherein Ris C-Calkyl or a group (A1) wherein R, Rand Rare each independently of the others hydrogen or C-Calkyl; wherein a compound of formula (Il) wherein Ris as defined for formula (I) and X is bromine or chlorine, is reacted with urea in the presence of a base and a catalytic amount of at least one palladium complex compound, wherein the palladium complex compound comprises at least one ferrocenyl-biphosphine ligand. |
