The Synthesis and Structure of Spiroimidazolones¹

Abstract

A number of derivatives of 1,3-diazaspiro[4.5] dec-l-enAne and 1,3-diaza~pir0[4.5]dec-2enAne were prepared by the interaction of appropriately Substituted 1-aminocyclohexanecarboxamidea and ethyl orthoformate. The structure of these spiroimidazolones was confirmed by chemical interconversions to known materiala and by examination of their ultraviolet and infrared spectra. Two compounds previously* reported to possess the spiroimidamlone structure appear to be the isomeric 1-formylaminocyclohexanecarbonitrilea XI1 and XIII.As part of a program directed toward the synthesis of central nervous system depressants we investigated a series of spiroimidazolones of types (6) We are indebted to Dr. W. S. Waring, Imperial Chemical Industries, Limited, Pharmaceutical Division, Alderley Park, Maccledield, Cheshire, Great Britain, for supplying a number of samplea for purposes of comparison and for communicating to us spectral data which corroborated our findings. NOVEMBEB 1961 SYNTHESU AND STBU-OF SPIBOIMIDUOLONES

Structural Characterization of 4-Cyanoimidazolium-5-olate, 4,4-Diphenyl-5-imidazolinone, and 4,5-Dicyanoimidazole. A Novel Mesoionic Compound and Decoding of Intermolecular Hydrogen Bonds

“…The large and intense signal at 1625 cm -1 may be assigned to the stretching of the carbon−oxygen bond. In the IR spectrum (KBr) of compound 4 the carbonyl absorbs at 1725 cm -1 , in agreement with data reported by Schipper et al, who assigned to compound 4 the unconjugated structure; the corresponding value for the conjugated tautomer is expected at 1710−1725 cm -1 . , The comparison of the absorption at 1625 cm -1 of compound 3 with the CO stretching of compound 4 discounts structures 3a − c and sustains the mesoionic structure 3h in the solid state, in accordance with data reported for the oxazol-5-ones …”

Thiohydantoins. IX. Tautomerism of some Methylation Products

“…Comparison of the spectra of 4 and 5 (X = 0 ) shows that the stretching frequencies of C=O and C=N are higher for the former compound, the values for both compounds being close to those for similar compounds already reported (3,9,10). In the more polar solvent, dimethyl sulfoxide, peaks indicative of both 1 and 2 (X = 0) are present, and examination of the peak intensities (Table 2) indicates that the proportion of 1 : 2 (X = 0 ) is roughly 60 : 40.…”

Structures and chromotropic properties of imidazole derivatives produced from 3,6-bis(4,5-diphenyl-2H-imidazol-2-ylidene)cyclohexa-1,4-diene

“…The imidazolone derivative (4) was oxidized by lead dioxide in benzene to give a dimer (7); the imidazolone (6) did not undergo oxidation, but lophine (8) was oxidized by lead dioxide to yield a dimer (10). Although compound (4) has two imino protons, only the imino proton of the imidazole (7) in KBr showed vNH at 3 450 cm-', vco at 1745 and no absorption at around 1 700 cm-l.…”