Cyclic biaryl phosphines as ligands for palladium-containing catalysts in cross-coupling reactions

A phosphine of formula (1)

• wherein
• Q is SiR3R4, GeR3R4, SnR3R4, AsR3 or Se;
• m is 0, 1, 2 or 3;
• n is 0, 1, 2 or 3;
• under the proviso that m+n≥1;
• the groups R are, independently of each other, a hydrogen atom or a C1-4 alkyl;
• or two groups R that bind to the same carbon atom are in each case a divalent alkylene group and together with the carbon atom to which they are bound form a 4- to 7-membered ring;
• or, under the proviso that m+n≥2, two groups R that bind to different carbon atoms are in each case a divalent alkylene group and together with the carbon atoms to which they are bound form a 4- to 7-membered ring;
• Ar1 is an aryl optionally substituted with one or more C1-6 alkyl groups;
• Ar2 is an aryl optionally substituted with one or more C1-6 alkyl groups;
• R3 and R4 are, independently of each other, a C1-4 alkyl, a C5-7 cycloalkyl or an aryl;
• or R3 and R4 are in each case a divalent alkylene group and together with the Si, Ge or Sn atom form a 4- to 7-membered ring.