Organoboron Derivatives of 1,8-Bis(dimethylamino)naphthalene: Synthesis, Structure, Stability, and Reactivity

A series of ortho-, meta-, and para-boronic acids and their pinacol esters of 1,8-bis(dimethylamino)naphthalene (DMAN), including the very first naphtho[1,8-cd][1,2,6]oxadiborinine-based proton sponge, were synthesized with moderate to good yields. The ease of deborylation of sterically hindered ortho-boronic acids of DMAN was demonstrated. DMAN-based 3,6-diboronic acid and its pinacol ester-valuable precursors for meta-derivatives of the naphthalene proton sponge-were prepared and utilized for the synthesis of 3,6-diiodoDMAN. Obtained acids and esters were tested for common palladium and copper catalyzed couplings.

Automated summary

A series of boronic acids and their esters derived from DMAN were synthesized, including a novel naphtho[1,8-cd][1,2,6]oxadiborinine-based proton sponge. The synthesis yields were moderate to good, and the deborylation of ortho-boronic acids of DMAN was demonstrated. The prepared 3,6-diboronic acid and its esters were used to synthesize 3,6-diiodoDMAN, and they were tested for common palladium and copper catalyzed couplings.