Enantiospecific Synthesis of ortho-Substituted Benzylic Boronic Esters by a 1,2-Metalate Rearrangement/1,3-Borotropic Shift Sequence

Enantiospecific Synthesis of ortho-Substituted Benzylic Boronic Esters by a 1,2-Metalate Rearrangement/1,3-Borotropic Shift Sequence

Coupling reactions between benzylamines and boronic esters have been investigated. ortho-Lithiated benzylamines react with boronic esters and a N-activator to afford ortho-substituted benzylic boronic esters with formal 1,1'-benzylidene insertion into the C-B bond. The reaction occurs by a SN2' elimination and 1,2-metalate rearrangement of the N-activated boronate complex to afford a dearomatiz...

Enantiospecific sp2–sp3 Coupling of ortho‐ and para‐Phenols with Secondary and Tertiary Boronic Esters

The coupling of ortho- and para-phenols with secondary and tertiary boronic esters has been explored. In the case of para-substituted phenols, after reaction of a dilithio phenolate species with a boronic ester, treatment with Ph3 BiF2 or Martin's sulfurane gave the coupled product with complete enantiospecificity. The methodology was applied to the synthesis of the broad spectrum antibacterial...

Enantiospecific, regioselective cross-coupling reactions of secondary allylic boronic esters.

Synthesis of sterically encumbered C10-arylated benzo[h]quinolines using ortho-substituted aryl boronic acids.

The challenging coupling of 10-halobenzo[h]quinolines with ortho-substituted aryl boronic acids has been achieved using Pd(OAc)(2)/P(O)Ph(3) as the catalytic system. High yields were obtained for diversely functionalised substrates under mild reaction conditions.

Development of Enantiospecific Coupling of Secondary and Tertiary Boronic Esters with Aromatic Compounds

The stereospecific cross-coupling of secondary boronic esters with sp(2) electrophiles (Suzuki-Miyaura reaction) is a long-standing problem in synthesis, but progress has been achieved in specific cases using palladium catalysis. However, related couplings with tertiary boronic esters are not currently achievable. To address this general problem, we have focused on an alternative method exploit...