Preparation from Aryl Halides and Sulfonates by Cross-coupling

Preparation from Aryl Halides and Sulfonates by Cross-coupling 

Yamamoto has reported the synthesis of (4-boronylphenyl)alanine (BPA), used dinically for treatment of malignant melanoma and brain tumors in neutron capture therapy by Pd-catalyzed coupling of triflate 47 with the diboron derivative 48 [22]. The boronic ester 49 could be easily cleaved by hydrogenolysis to give I-BPA 50 in 74% yield, whereas the corresponding pinacol ester yielded mixture 

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