A zwitterion produced by a strong intramolecular N→B interaction in 1-hydroxy-2-(pyridin-2-ylcarbonyl)benzo[d][1,2,3]diazaborinine

2015 ◽  
Vol 71 (12) ◽  
pp. 1085-1088 ◽  
Author(s):  
Evan A. Sarina ◽  
Marilyn M. Olmstead ◽  
Divya Kanichar ◽  
Michael P. Groziak
Keyword(s):  
Crystal Structure ◽  
Chemical Shift ◽  
Structure Analysis ◽  
Lewis Acid ◽  
Crystal Structure Analysis ◽  
Deuterium Exchange ◽  
The Other ◽  
Nmr Spectrum ◽  
H Nmr

2-Acylated 2,3,1-benzodiazaborines can display unusual structures and reactivities. The crystal structure analysis of the boron heterocycle obtained by condensing 2-formylphenylboronic acid and picolinohydrazide reveals it to be an N→B-chelated zwitterionic tetracycle (systematic name: 1-hydroxy-11-oxo-9,10,17λ5-triaza-1λ4-boratetracyclo[8.7.0.02,7.012,17]heptadeca-3,5,7,12,14,16-hexaen-17-ylium-1-uide), C13H10BN3O2, produced by the intramolecular addition of the Lewis basic picolinoyl N atom of 1-hydroxy-2-(pyridin-2-ylcarbonyl)benzo[d][1,2,3]diazaborinine to the boron heterocycle B atom acting as a Lewis acid. Neither of the other two pyridinylcarbonyl isomers (viz. nicotinoyl and isonicotinoyl) are able to adopt such a structure for geometric reasons. A favored yet reversible chelation equilibrium provides an explanation for the slow D2O exchange observed for the OH resonance in the1H NMR spectrum, as well as for its unusual upfield chemical shift. Deuterium exchange may take place solely in the minor open (unchelated) species present in solution.

Das 7,8-Benzo-5-chloro-1,4,4-trimethyl-1-aza-4-azonia-6,9-dioxa-5 λ5-phosphaspiro[4.4]nonanyl-Kation: Röntgenstrukturanalyse und temperaturabhängige 1H-NMR-Spektren: The 7, 8-Benzo-5-chloro-1,4,4-trimethyl-1-aza-4-azonia-6,9-dioxa-5 λ).5-phosphaspiro[4.4]nonanyl Cation: X-Ray Crystal Structure Determination and Variable 1H NMR Spectra

1992 ◽  
Vol 47 (6) ◽  
pp. 755-759 ◽  
Author(s):  
Thomas Kaukorat ◽  
Peter G. Jones ◽  
Reinhard Schmutzler
Keyword(s):  
Crystal Structure ◽  
1H Nmr ◽  
Nmr Spectra ◽  
Crystal Structure Analysis ◽  
Acceptor Interaction ◽  
Nmr Spectrum ◽  
X Ray ◽  
H Nmr ◽  
Trigonal Bipyramidal ◽  
Donor Acceptor

The 1H NMR spectrum of the spirophosphorane 3 at room temperature indicates dynamic behaviour of the cation. The low-temperature 1H NMR spectra of 3 exhibit two sets of doublets for the protons of the diastereotopic N(CH3)2 groups. The free enthalpy of activation for the dynamic process was determined (58.6 KJ/mole). In the reaction of 3 with sodium tetraphenylborate the crystalline compound, 4, involving the non-coordinating anion, [B(C6H5)4]-, was obtained. The X-ray crystal structure analysis of 4 reveals the presence of a five-membered ring, formally as a result of intramolecular donor-acceptor interaction between the nitrogen atom of the N(CH3)2 group and phosphorus. The geometry at phosphorus deviates somewhat from ideal trigonal bipyramidal.

Structures and photochemistry of 1,5-disubstituted dibenzobarrelenes

1996 ◽  
Vol 52 (1) ◽  
pp. 151-158
Author(s):  
R. Jones ◽  
S. J. Rettig ◽  
J. R. Scheffer ◽  
J. Trotter ◽  
J. Yang
Keyword(s):  
Crystal Structure ◽  
Double Bond ◽  
Crystal Structures ◽  
Structure Analysis ◽  
Crystal Structure Analysis ◽  
The Other ◽  
Steric Effects ◽  
Molecular And Crystal Structures ◽  
Electronic And Steric Effects

The effect of 1,5-disubstitution on the photochemistry of 9,10-ethenoanthracene-11,12-diesters has been studied and correlated with the crystal structures determined for several derivatives; photoproduct structures have been established from a crystal structure analysis of one of the products and from NMR correlations. The crystals studied are: (1)-Cl, dimethyl 1,5-dichloro-9,10-dihydro-9,10-ethenoanthracene-11,12-dicarboxylate, C20H14Cl2O4, P21/n; (1)-CN, 1,5-dicyano derivative, C22H14N2O4, P21/n; (1)-CN.0.5p-xylene, C22H14N2O4.0.5C8H10, P21/c; (1)-CN.xxylene, C22H14N2O4.xC8H10, P21/n; (1)-OMe, 1,5-dimethoxy derivative, C22H20O6, P{\bar 1}; (2b)-Cl, C20H14C12O4, dimethyl 1,5-dichloro-4b,8b,8c,8d-tetrahydrodibenzo[a, f]cyclopropa[c,d]pentalene-8c,8d-dicarboxylate, Pna21. The dibenzobarrelene molecules all have geometries and dimensions similar to those of related materials. In particular, the orientations of the two ester groups in each molecule differ, one being in general almost fully conjugated with the C(11)=C(12) double bond and the other almost non-conjugated. Relationships are sought between the ratios of the two regioisomeric photoproducts and molecular and crystal structures; both electronic and steric effects are considered, but no one effect seems to dominate.

Synthesis and Characterization of Ionic Liquid 1-Propargly-3-Methylimidazolium Chlorate

2012 ◽  
Vol 427 ◽  
pp. 173-178
Author(s):  
Ying Jie Cai ◽  
Xiu Jie Ji ◽  
Bo Wen Cheng ◽  
Dong Dong Xie ◽  
Qiu Ling Wang ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Ionic Liquid ◽  
Structure Analysis ◽  
Crystal Structure Analysis ◽  
High Yield ◽  
Imidazolium Ionic Liquid ◽  
H Nmr ◽  
Compound C ◽  
And Function ◽  
Relationship Of

The title compound (C7H9ClN2, Mr = 156.61), an imidazolium ionic liquid with alkynyl, was synthesized by an improved method in high yield. FT-IR,1H NMR,13C NMR and elemental analysis were performed to characterize the molecule of the ionic liquid, and its crystal structure was determined by single-crystal X-ray structure analysis. The results indicate that the improved procedure is very feasible and 96% yield. The crystal structure analysis will be conducive to clarify the relationship of structure and function for ionic liquid with alkynyl the compound.

Substituent effects in solution speciation of the mononuclear and dinuclear trimethylplatinum(iv) iodide complexes of pyridines

2015 ◽  
Vol 39 (5) ◽  
pp. 3536-3542 ◽  
Author(s):  
Biswa Nath Ghosh ◽  
Dieter Lentz ◽  
Sabine Schlecht
Keyword(s):  
Crystal Structure ◽  
Nmr Spectroscopy ◽  
Structure Analysis ◽  
Substituent Effects ◽  
Crystal Structure Analysis ◽  
X Ray ◽  
H Nmr ◽  
Pyridine Ligands ◽  
Solution Speciation

A series of mononuclear and dinuclear trimethylplatinum(iv) iodide complexes of pyridine ligands have been synthesized and characterized using 1H-NMR spectroscopy and X-ray crystal structure analysis.

Molekülstruktur des 7-Methyl-1.3.5-triaza-7-phosphaadamantan-7-ium-tetrafluoroborats. Darstellung und Charakterisierung des 7-Methyl-1.3.5-triaza-7-phospha-tricyclo[3.3.2.13,7]-undecan-7-ium-iodids/Molecular Structure of 7-Methyl-1 ,3,5-triaza-7-phosphaadamantane-7-ium-tetrafluoroborate. Preparation and Characterization of 7-Methyl-1,3,5-triaza-7-phospha-tricyclo[3,3,2,1 3,7]-undecan-7-ium-iodide

1978 ◽  
Vol 33 (11) ◽  
pp. 1257-1262 ◽  
Author(s):  
Kurt H. Jogun ◽  
John J. Stezowski ◽  
Ekkehard Fluck ◽  
Hans-Jürgen Weißgraeber
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Nmr Spectroscopy ◽  
Structure Analysis ◽  
Ir Spectrum ◽  
Parent Compound ◽  
Crystal Structure Analysis ◽  
H Nmr

Abstract 7-Methyl-1,3,5-triaza-7-phosphaadamantane-7-ium-tetrafluoroborate (2b) has been synthesized and characterized by crystal structure analysis. The crystal structure is interpreted in comparison with the parent compound 1,3,5-triaza-7-phosphaadamantane, and its 7-oxide and 7-sulfide. 7-Methyl-1,3,5-triaza-7-phospha-tricyclo[3,3,2,1 3,7]-undecan-7-ium-iodide (6) has been prepared and characterized by 31P, 13C, and 1H NMR spectroscopy and by its IR spectrum.

Mononuclear and dinuclear trimethylplatinum(iv) iodide complexes of 3-substituted pyridines

2017 ◽  
Vol 41 (9) ◽  
pp. 3498-3507 ◽  
Author(s):  
Biswa Nath Ghosh ◽  
Sabine Schlecht ◽  
Antonio Bauzá ◽  
Antonio Frontera
Keyword(s):  
Crystal Structure ◽  
Nmr Spectroscopy ◽  
Structure Analysis ◽  
Crystal Structure Analysis ◽  
X Ray ◽  
H Nmr ◽  
Substituted Pyridines

A series of mononuclear and dinuclear trimethylplatinum(iv) complexes of 3-substituted pyridines has been studied by 1H NMR spectroscopy, DFT computational and X-ray crystal structure analysis.

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