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The 1H and 13C NMR spectra of two stereoisomeric bis-Tröger's bases and four stereoisomeric tris-Tröger's bases asymmetrically substituted on the external aromatic rings were recorded and the corresponding signals assigned. The relative configuration of the stereogenic units has been unequivocally determined on the basis of homoallylic couplings and NOE experiments. Copyright © 2005 John Wiley & Sons, Ltd.

Several scalar coupling constants (mainly 31P, 31P) were calculated for 10 cyclotriphosphazenes and compared with experimental results when available. Although the experimental values cannot be reproduced, the calculated values are proportional to the experimental values. Some difficult cases, such as 19F, 19F couplings, are discussed. Copyright © 2005 John Wiley & Sons, Ltd.

When 1,4-bis-ethoxymethylen-2,3-butanedione 2 reacts with hydrazine, following a slightly modified Effenberger's procedure, other compounds than the expected 3,5′-bipyrazole 1 are obtained. This paper describes the isolation, besides 1, of two pyridazinones and one 6H-6,7-dihydropyrazolo[1,5-d]-1,2,4-triazine and the determination of their structure by mass spectrometry and by 1H and 13C NMR.

1-Hydroxymethylindazole and 1-hydroxymethylbenzotriazole have been studied in solution by 1H, 13C and 15N NMR spectroscopy and the X-ray structure of the second compound determined. DFT and GIAO calculations have been used to discuss geometries, energies (comparatively with 2-substituted isomers) and NMR chemical shifts.

Three new C-bonded cyclotriphosphazenes, N3P3(2-thienyl)6{,} 2{,} N3P3(3-thienyl)6{,} 4{,} and N3P3(3{,}3prime or minute]-bithienyl-2,2prime or minute-ylene)3{,} 6{,} have been prepared by two new synthetic procedures and are the first examples of non-spiro and trispirocyclotriphosphazene derivatives composed of thiophene and 3{,}3prime or minute-dithiophene substituents{,} respectively. Their 1H{,} 13C and 31P NMR parameters are given. The solid state structures of 2{,} 4 and 6 have been determined by X-ray crystallography.