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T Hökelek

Publications and source records attributed to T Hökelek.

8 recordsLinked to original sources
PubMed2001

trans-2,4,4,6,8,8-Hexamorpholino-2,6-bis(n-propylamino)cyclo-2lambda5,4lambda5,6lambda5,8lambda5-tetraphosphazatetraene.

The title compound, C(30)H(64)N(12)O(6)P(4), consists of a centrosymmetric chair-shaped cyclic tetrameric phosphazene ring with six bulky morpholino and two n-propylamino side groups. The two n-propylamino side groups are in trans positions. The bulky substituents mainly determine the eight-membered-ring conformation. The endocyclic N-P-N angles around the P atoms having different substituents are not the same as the P-N-P angles of the macrocyclic ring.

Aza Compounds↗
PubMed2001

4-([(1E)-(2-Hydroxyphenyl)methylidene]amino)-1,5-dimethyl-2-phenyl-2,3-dihydro-1H-pyrazol-3-one.

In the title compound, C18H17N3O2, a strong intramolecular O-H...N hydrogen bond [N...O 2.607 (3), O-H 0.97 (3) and H...N 1.71 (3) A, and O-H...N 153 (2) degrees ] was observed, which leads to a unique phenol-imine tautomerism in the solid state. The C=N imine bond distance and the C-N-C bond angle [1.287 (2) A and 121.7 (1) degrees, respectively] indicate the existence of this phenol-imine tautomer. In solution, the phenol-imine tautomer of the title free Schiff base ligand is dominant in both polar and non-polar solvents, as supported by 1H NMR and UV-visible spectroscopic data.

Journal Article↗
PubMed2001

4-Methylcarbazole-3-carboxylic acid.

The title compound, C(14)H(11)NO(2), consists of a carbazole skeleton with carboxylic acid and methyl groups at positions 3 and 4, respectively. Molecules are linked about inversion centres by O-H.O hydrogen bonds [O.O 2.620 (3) A] to form centrosymmetric dimers.

Journal Article↗
PubMed2000

N-[Bis(2,4,6-trimethylphenoxy)phosphinoyl]-P,P,P-tris(2,4, 6-trimethylphenoxy)phosphazene.

The title compound, C(45)H(55)NO(6)P(2), consists of an acyclic P=N-P(O) monophosphazene chain and five bulky 2,4,6-trimethylphenoxy side groups which predominantly determine the molecular shape. Although the P-N single [1.586 (3) A] and P=N double [1.517 (3) A] bonds are significantly different from each other, both are substantially shorter than the ideal P-N single bond. The P-N-P angle [146.0 (2) degrees ] corresponds to the upper limit reported for acyclic phosphazene derivatives in the literature.

Journal Article↗