Hemilabile methoxy groups

The rationale behind the introduction of the ortto-methoxy group is its ability to behave as a hemilabile ligand, which is likely to stabilise the paUadium(O) catalyst species - after reductive elimination of the product in the catalytic cycle - by intermittently occupying the otherwise empty coordination sites preventing formation of palladium black. 

The reactions were conducted at 100 °C employing PdlOAc) and K COj or CS2CO3 as the base. It was noted that ligands bearing a hemilabile donor group such as OMe in MOP (13) 2-(Diphenylphosphino)-2 -methoxy-l,l -binaphthyl (see Figure 13.2) were more efficient, as they provide an open coordination site for the secondary amide. 

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