Sulfonated phosphine and other ligands

Direct sulfonation of aryl group by fuming sulfuric acid (oleum) followed by neutralization to give the sulfonyl group at meta position.  

Remote sulfonation at an arene not linked to P carried out under milder conditions (cone. H2SO4, rt).  

Nucleophilic substitution of phosphide ion on fluoroarene sulfonic acid resulting in the sulfonyl group at ortho or para position or both.  

Reaction of diarylphosphide with haloalkyl sulfonic acid salt or sultone giving diaryl alkyl phosphine.  

Cross-coupling of substituted iodobenzenes with Ph2PH catalyzed by Pd(OAc)2.  

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