Synthesis of furan derivatives. LXXXVII. Kinetic studies of the thermal Curtius rearrangement of 2-benzofuroyl azide and related compounds.

D & TOF‐SIMS failure analysis of P‐buried layer from BiCMOS transistors

“…In contrast, 2‐iodopyridine produced a mixture of products under similar reaction conditions, including 2‐PyNCO, 2‐PyCONH 2 , and 2‐PyNH 2 . This outcome is likely due to the lower thermal stability of 2‐PyCON 3 16 and, possibly, to the well‐known17 dimerization of 2‐pyridyl palladium derivatives through the N atoms of the pyridine ring.…”

Palladium‐Catalyzed Aromatic Azidocarbonylation

“…This outcome is likely due to the lower thermal stability of 2-PyCON 3 [16] and, possibly, to the well-known [17] dimerization of 2-pyridyl palladium derivatives through the N atoms of the pyridine ring. In contrast, 2-iodopyridine produced a mixture of products under similar reaction conditions, including 2-PyNCO, 2-PyCONH 2 , and 2-PyNH 2 .…”

“…[16,18] As a result, an ortho-substituted aroyl azide originally produced in the reaction quickly rearranges to the corresponding isocyanate that may be partially converted into ArNH 2 under the reaction conditions. The reaction was more selective toward the formation of ureas for 2-iodoanisole and 1-iodonaphthalene: N,N'-bis(1-naphthyl)urea (3 a; see Scheme 2) was obtained pure in 76 % yield and 2-iodoanisole gave N,N'-bis(2-methoxyphenyl)urea (3 b) that was isolated in 74 % yield (ca.…”

Palladium‐Catalyzed Aromatic Azidocarbonylation

“…In contrast, 2-iodopyridine produced a mixture of products under similar reaction conditions, including 2-PyNCO, 2-PyCONH 2 , and 2-PyNH 2 . This outcome is likely due to the lower thermal stability of 2-PyCON 3 [16] and, possibly, to the well-known [17] dimerization of 2-pyridyl palladium derivatives through the N atoms of the pyridine ring.…”

“…The different reaction outcome for 2-substituted iodoarene substrates is hardly surprising because ArCON 3 bearing an ortho substituent are 50-200 times more reactive toward the Curtius rearrangement than their m and p isomers. [16,18] As a result, an ortho-substituted aroyl azide originally produced in the reaction quickly rearranges to the corresponding isocyanate that may be partially converted into ArNH 2 under the reaction conditions. The aniline then adds to the as yet unreacted ArNCO to form the urea (Scheme 2).…”