Synthesis and Structural Assignment of Oxanilo-N-arylhydrazonoyl Chlorides

Synthesis of nitrogen-containing dispiroheterocycles (1) using nitrilimines

“…The hydrazonoyl halides 1a-k were prepared by a modified literature procedure, [18][19][20][21][22] and the nitrilimines 2 were generated in situ from 1 by reaction with triethylamine (Et 3 N). The nonisolable nitrilimines 2 reacted readily with 1,4-cyclohexanedione methylhydrazone 3 affording the corresponding 1,2,4,5,10,11,13,14-octaazadispiro[5.2.5.2]hexadeca-2,12-dienes 4a-k (Scheme 1), owing to the high nucleophilicity of the nitrogen atom carrying the methyl group.…”

Heterocyclic synthesis using nitrilimines: Part 10. Synthesis of 1-aryl-3-phenylaminocarbonyl-4,5-dihydro-1,4,5-triazin-6-ones

“…Elemental analysis were carried out at the microanalytical laboratory, University of Cairo, Giza, Egypt. The hydrazonoyl chlorides 1a-e 23,26,27 and α-amino ester hydrochlorides 3a-e 3 were prepared following reported procedures.…”

“…A main fragmentation mode of the closely related substituted 4,5-dihydro-1,2,4-triazin-6-ones was reported to involve hetero ringscission at the dotted lines as shown below (Scheme 2), leading to fragment ion M-105 as a base peak. 22,23 The spectra also displayed a significant ion corresponding to M-29. This ion might originate via expulsion of (HC=O) from the molecular ion.…”

Reactions of N-acylhydrazones with thionyl chloride

“…The presence of C=NNH moiety at the molecule gives the possibility of formation of (E) and (Z) isomers. It has been confirmed by spectroscopic studies 5,6 as well as X-ray diffraction analysis [6][7][8] that hydrazonoyl halides exist as (Z) isomers. Furthermore, it is known that (Z) isomers are thermodynamically more stable.…”