Process for the preparation of acylphosphines, acyl oxides and acyl sulfides

A process for the preparation of acylphosphine oxides and acylphosphine sulfides of formula IV

• n=1, m=2, and
• R1 is C1-C18alkyl, C2-C18alkyl which is interrupted by one or several non-successive O atoms;
• phenyl-substituted C1-C4alkyl, C2-C8alkenyl, phenyl, naphthyl, biphenyl, C5-C12cycloalkyl, the groups phenyl, naphthyl, biphenyl, C5-C12cycloalkyl being unsubstituted or substituted by one to five halogen, C1-C8alkyl, C1-C8alkylthio and/or C1-C8alkoxy;
• Z is O or S,
• R2 is C1-C18alkyl, C3-C12cycloalkyl, C2-C18alkenyl, phenyl, naphthyl, biphenyl, the groups phenyl, naphthyl, biphenyl being unsubstituted or substituted by one to four C1-C8alkyl, C1-C8alkoxy, C1-C8alkylthio and/or halogen;
• R3 is C1-C18alkyl, C2-C18alkyl which is interrupted by one or several non-successive O atoms;
• phenyl-substituted C1-C4alkyl, C2-C8alkenyl, phenyl, naphthyl, biphenyl, C5-C12cycloalkyl, the groups phenyl, naphthyl, biphenyl, C5-C12cycloalkyl being unsubstituted or substituted by one to five halogen, C1-C8alkyl, C1-C8alkylthio and/or C1-C8alkoxy;
• by
• (1) reacting organic phosphorus halides of formula II
• wherein R1, R3, n and m have the meaning cited above and Y is Br or Cl,
• with an alkali metal or with magnesium in combination with lithium, or with mixtures thereof, with or without a catalyst, and
• (2) subsequent reaction with m acid halides of formula III
• wherein R2, m and Y have the meaning cited above, and
• (3) oxidation or reaction with sulfur of the acylphosphine of formula I
• which is obtained by reaction (2),
• wherein R1, R2, R3, m and n have the meaning cited above,
• which process is carried out without isolation of the intermediates.