Structure of topological solitons in the Skyrme model

Patrice Lumumba Friendship of Nations University, Moscow. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 75, No. 3, pp. 353–360, June, 1988.     

Crystal and molecular structures of (9-methylfluoren-9-yl)trimethyltin and (fluoren-9-yl)trimethyltin

Conclusions An increase in the length of the Sn-C (fluorene) bond is not observed in crystals of 9-fluorenyl derivatives of tin, and the variation in the lengths of the Sn-Me bonds is similar to that found in other types of organotin compounds.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2054–2057, September, 1980.     

Heterocycles with a bridging nitrogen atom. 9. Recyclization of an oxazole fragment to a pyrrole fragment. Synthesis and crystal structure of 5-hexamethylenimino-2-p-nitrophenylindolyzine

X-ray diffraction structural analysis was used to determine the structure of 5-hexamethylenimino-2-p-nitrophenylindolyzine formed in the reaction of 5-methyl-2-p-nitrophenyloxazolo[3,2-a]pyridinium perchlorate with hexamethylenimine.For Communication 8, see [1].M. V. Lomonosov Moscow State University, 119899 Moscow. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 983–985, July, 1998.     

1,10‐Diaza‐18‐crown‐ether,Modified by Phosphonate Pendant Arms – Synthesis,Structure, and Picrate Extraction Properties

Reaction of O,O′‐diisopropyl‐3‐methyl‐1,2‐butadienylphosphonate with 1,10‐diaza‐18‐crown‐6 in the presence of a catalytic amount of iPrONa leads to the new crown‐ether derivative, containing phosphonate pendant arms ( L ). The structure of the compound obtained was investigated by single crystal X‐ray diffraction analysis, IR, ¹H and ³¹P{¹H} NMR spectroscopy, and microanalysis. In the crystal structure the side arms of L are in an anti disposition relative to the macrocyclic cavity. It was established that phosphorylation of 1,10‐diaza‐18‐crown‐6 by allenylphosphonate results in an increase of extraction of NaPic and KPic, whereas LiPic and NH₄Pic are extracted practically in the same level.     

X-ray mapping in heterocyclic design: II. Diffractometric study of crystalline 2-oxo-2,3-dihydroimidazo[1,2-a]pyridine hydrochloride

The crystal structure of 2-oxo-2,3-dihydroimidazo[1,2-a]pyridine hydrochloride, C₇H₇ClN₂O, is determined by X-ray diffraction. The structure is solved by the direct method and refined by the least-squares procedure to R = 0.0408. The alternation of bond lengths in the molecule is inconsiderable, but does not disappear completely, since no aromatization occurs upon formation of the bicycle from the molecule. This structural change is apparently due to the increased conjugation of the NH group with the pyridine residue of the bicycle. One of the specific structural features of the salt is the formation of the N⁺-HïCl^? hydrogen bond (N-H, 0.792 Å; H?Cl, 2.260 Å; and N-H?Cl, 171.2°).     

Dynamical toroidal Hopfions in a ferromagnet with easy-axis anisotropy

Three-dimensional toroidal precession solitons with a nonzero Hopf index, which uniformly move along the anisotropy axis in a uniaxial ferromagnet, have been found. The structure and existence region of the solitons have been numerically determined by solving the Landau-Lifshitz equation.     

Reactions of allenylphosphonates with trioxatridecanediamine

Russian Journal of General Chemistry -