The actually direct Suzuki−Miyaura coupling with "protected" R−B(dan) (dan = naphthalene-1,8-diaminato) was demonstrated to smoothly occur without in situ deprotection of the B(dan) moiety. The use of t-BuOK (Ba(OH) 2 in some cases) as a base under anhydrous conditions is the key to the successful cross-coupling, where R−B(dan) is readily converted into a transmetalation-active borate-form, regardless of the well-accepted diminished boron-Lewis acidity.

H–B(dan) serves as a B(dan) electrophile to give directly R–B(dan) by the reaction with Grignard reagents under transition metal-free conditions.

Unsymmetrical B(MIDA)-containing diborons of potential synthetic utility were found to be synthesized from the readily available (neop)B–B(neop) and (HO) 2 B–B(OH) 2 , and the procedure was extended to the generation of symmetrical (MIDA)B–B(MIDA). NMR and X-ray crystal structure studies revealed that B(MIDA) units of all of the diborons obtained in this study were in rigid tetrahedral environment.

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