Concentration‐Dependent Thermal Isomerization of Nitrile N‐Oxide

Abstract

Kinetically stabilized nitrile N-oxides (NOs) have been regarded as viable tools for the postpolymerization functionalization of common polymers. However, thermal isomerization of NO to isocyanate restricts the applications of NO to industrial use. The reaction mechanism for the thermal isomerization has not been systematically evaluated. Herein, we report the concentration-dependent isomerization of NOs for the first time. The time-course plots suggest that the isomerization of NO [a

Synthesis and Reactions of Homoditopic Stable Nitrile N‐Oxide as a Powerful Tool for Catalyst‐Free Constructions of Macromolecular Architectures

“…However, the reaction of nitrile N-oxide tends to involve undesirable side reactions with nucleophiles [14] and self-reactions such as dimerization, [16] oligomerization, [17] and isomerization. [18][19][20][21][22][23] Nitrile N-oxide can be kinetically stabilized with neighboring bulky substituents such as an orthosubstituent for aromatic nitrile N-oxide and a quaternary carbon center adjacent to aliphatic nitrile N-oxide. With this concept, we have developed homoditopic stable nitrile N-oxides as a ligation tool, which enables the catalyst-free polymerization of bisdipolarophiles [24,25] and the cross-linking reactions of common polymers.…”

Rearrangements of Aromatic Nitrile Oxides and Nitrile Ylides: Potential Ring Expansion to Cycloheptatetraene Derivatives Mimicking Arylcarbenes

“…Oxazirines [19d,e,k] and acylnitrenes [19d,k] have been suggested as reactive intermediates, as has a dyotropic rearrangement, [19e,h] in which the group R and the oxygen atom migrate simultaneously. For reactions in solution it has been suggested that aggregates or oligomers are involved [19j,n] …”