Unusual (Z)-selective palladium(ii)-catalysed addition of aryl boronic acids to vinylaziridines

Abstract

The palladium(II)-catalysed addition of arylboronic acids to vinylaziridines has been developed. This reaction proceeds via an insertion/ring-opening process to provide (Z)-allylsulfonamides preferentially. This stereoselectivity is complimentary to existing methods that typically proceed via a SN2' mechanism to yield (E)-allylsulfonamides. Electron-deficient arylboronic acids were the optimum substrates for this reaction, while electron-donating groups on the aromatic ring of the boronic acids resulted in moderate yields.

Oxidative aminoaziridination: past, present, and future

“…8 However, a huge excess of buta-1,3-diene afforded 1-phthalimido-2-vinylaziridine in 83% yield. 30 In contrast, reacting conjugated alk-1-en-3-ynes with API (Scheme 8) led to 2-alkynyl-1-phthalimidoaziridines with three endothermic fragments (a strained three-membered ring, С≡С and N-N bonds) in high yields even when an equimolar ratio of reagents is used. 31,32…”

Palladium‐Catalyzed Regioselective and Stereospecific Ring‐Opening Suzuki‐Miyaura Arylative Cross‐Coupling of 2‐Arylazetidines with Arylboronic Acids

“…Over the last several years, various transition‐metal‐catalyzed ring‐opening cross‐coupling of aziridines has been extensively developed to form a C−C, [11–16] C−B, [17,18] and C−Si bond [19,20] . The significant features of these ring‐opening cross‐couplings include the high regioselectivity governed by the oxidative addition event.…”

Catalyst-controlled regiodivergent ring-opening C(sp3)–Si bond-forming reactions of 2-arylaziridines with silylborane enabled by synergistic palladium/copper dual catalysis

“…Aziridines have emerged as relatively new alkyl electrophiles in transition-metal-catalyzed regioselective ring-opening C–C13–18 and C–B19,20 cross-couplings with organoboron and organozinc nucleophiles to give β-organo- and borylated alkylamines, respectively. In conjunction with the fact that alkylamines bearing a C(sp 3 )–Si bond have been recognized as unique bioisosteres of pharmacological agents in medicinal chemistry,21 regiodivergent ring-opening C(sp 3 )–Si cross-coupling of aziridines with a silyl (pro)nucleophile would open up a new avenue to the preparation of a set of regioisomeric β-silyl-alkylamines.…”