Synthesis and some transformations of polybrominated quinone diazides

Transition‐Metal‐Free C(sp2)–C(sp2) Cross‐Coupling of Diazo Quinones with Catechol Boronic Esters

“…We propose that the B-O interaction might facilitate the generation of the quinone carbene.This is because generating ac arbene through the direct thermolysis of ad iazo quinone commonly requires ahigh temperature (above 70 8 8C), [15] and the reaction of donor-type TMS diazomethane (TMSCHN 2 ) with 2g-1 would require heating (60 8 8C) over an extended time period (15 h), [11k, 16] unlike the milder reaction conditions reported in this work. Thea ddition of 3equiv of 1a significantly inhibited the reaction, leading to al ow product Table 2: Cross-coupling of diazo quinones with aryl boronic esters.…”

Transition‐Metal‐Free C(sp2)–C(sp2) Cross‐Coupling of Diazo Quinones with Catechol Boronic Esters

“…We propose that the B-O interaction might facilitate the generation of the quinone carbene.This is because generating ac arbene through the direct thermolysis of ad iazo quinone commonly requires ahigh temperature (above 70 8 8C), [15] and the reaction of donor-type TMS diazomethane (TMSCHN 2 ) with 2g-1 would require heating (60 8 8C) over an extended time period (15 h), [11k, 16] unlike the milder reaction conditions reported in this work. Thea ddition of 3equiv of 1a significantly inhibited the reaction, leading to al ow product Tabelle 2: Cross-coupling of diazo quinones with aryl boronic esters.…”

Diazocarbonyl and Related Compounds in the Synthesis of Azoles

“…The reaction between polybrominated o -quinone diazides 25 (available via diazotization of aminophenols 24 ) and nitriles 26 leading to benzoxazoles 27 was described in 2017 by Vasin and co-workers [ 30 ]. The reaction proceeded on conventional heating, albeit in modest yields ( Scheme 7 ).…”