CO-ORDINATION COMPLEXES OF TITANIUM (IV) HALIDES: 1. PREPARATION AND INFRARED SPECTRA OF THE COMPLEXES OF TITANIUM (IV) HALIDES WITH N,N-DIMETHYL AND N,N-DIPHENYL FORMAMIDE

1960 ◽  
Vol 38 (8) ◽  
pp. 1331-1338 ◽  
Author(s):  
Jacques Archambault ◽  
Roland Rivest
Keyword(s):  
Double Bond ◽  
Carbonyl Group ◽  
Infrared Spectra ◽  
Dimethyl Formamide ◽  
Double Bond Character ◽  
Positive Shift ◽  
Negative Shift ◽  
Oxygen Bond ◽  
Bond Character

Co-ordination complexes of titanium (IV) halides with N,N-dimethyl formamide and N,N-diphenyl formamide have been prepared and their infrared spectra have been measured. In all these complexes, there is a metal-to-oxygen bond as evidenced in the infrared spectra by a negative shift of the carbonyl stretching frequency and a positive shift of the CN stretching frequency. The relative values of these shifts and the ease of decomposition observed for these complexes indicate that their stability decreases with decreasing the electronegativity of the halide bonded to titanium (IV).In the complexes of N,N-diphenyl formamide, the effect of the conjugated phenyl groups has been observed. In these complexes the decrease of double-bond character of the carbonyl group and the increase of double-bond character of the CN group, resulting from the metal-to-oxygen co-ordination bond, are quite larger than in the complexes of N,N-dimethyl formamide.

THE SOLVOLYSIS OF THE ALPHA- AND BETA-3,4,6-TRI-O-ACETYL-D-GLUCOPYRANOSYL CHLORIDES

1955 ◽  
Vol 33 (1) ◽  
pp. 128-133 ◽  
Author(s):  
R. U. Lemieux ◽  
G. Huber
Keyword(s):  
Acetic Acid ◽  
Double Bond ◽  
Positive Charge ◽  
Main Reaction ◽  
Main Reaction Product ◽  
Double Bond Character ◽  
Ionic Reactions ◽  
Oxygen Bond ◽  
Bond Character ◽  
Anomeric Center

3,4,6-Tri-O-acetyl-β-D-glucopyranosyl chloride was found to undergo solvolysis in acetic acid to form 1,3,4,6-tetra-O-acetyl-α-D-glucopyranose as the main reaction product. The much less reactive anomeric α-chloride also appeared to undergo solvolysis with extensive inversion of the anomeric center. It is submitted that the tendencies for inversion obtained in these ionic reactions are due to the conformations imposed on the intermediate ions through distribution of the positive charge to the ring oxygen and the consequent introduction of double-bond character to the carbon-1 to ring-oxygen bond.

DONOR ACCEPTOR REACTIONS OF TITANIUM TETRACHLORIDE WITH FORMAMIDE AND N,N-DIMETHYL FORMAMIDE

1958 ◽  
Vol 36 (11) ◽  
pp. 1461-1466 ◽  
Author(s):  
Jacques Archambault ◽  
Roland Rivest
Keyword(s):  
Infrared Spectra ◽  
Titanium Tetrachloride ◽  
Dimethyl Formamide ◽  
Positive Shift ◽  
Negative Shift ◽  
Structural Formulas ◽  
Donor Acceptor

Co-ordination complexes of titanium tetrachloride with formamide and N,N-dimethyl formamide have been prepared. All the complexes found are explained through a co-ordination number of 6 for titanium (IV).The infrared spectra of these compounds were measured; a negative shift observed for the carbonyl frequency and a positive shift observed for what is thought to be the C—N frequency are explained by a co-ordination through the oxygen of these molecules. Structural formulas are proposed for the compounds obtained.

scholarly journals Crystal structure ofN′′-benzyl-N′′-[3-(benzyldimethylazaniumyl)propyl]-N,N,N′,N′-tetramethylguanidinium bis(tetraphenylborate)

2015 ◽  
Vol 71 (12) ◽  
pp. o1086-o1087
Author(s):  
Ioannis Tiritiris ◽  
Willi Kantlehner
Keyword(s):  
Crystal Structure ◽  
Double Bond ◽  
Positive Charge ◽  
Planar Geometry ◽  
Methyl Groups ◽  
Two Dimensional ◽  
Single Bond ◽  
Double Bond Character ◽  
Bond Lengths ◽  
Bond Character

In the crystal structure of the title salt, C24H38N42+·2C24H20B−, the C—N bond lengths in the central CN3unit of the guanidinium ion are 1.3364 (13), 1.3407 (13) and 1.3539 (13) Å, indicating partial double-bond character. The central C atom is bonded to the three N atoms in a nearly ideal trigonal–planar geometry and the positive charge is delocalized in the CN3plane. The bonds between the N atoms and the terminal methyl groups of the guanidinium moiety and the four C—N bonds to the central N atom of the (benzyldimethylazaniumyl)propyl group have single-bond character. In the crystal, C—H...π interactions between the guanidinium H atoms and the phenyl C atoms of the tetraphenylborate ions are present, leading to the formation of a two-dimensional supramolecular pattern parallel to theacplane.

scholarly journals 3-Phenyl-N,N,N′,N′-tetramethyl-1-ethyne-1-carboximidamidium bromide

2012 ◽  
Vol 68 (6) ◽  
pp. o1812-o1812 ◽  
Author(s):  
Ioannis Tiritiris ◽  
Willi Kantlehner
Keyword(s):  
Double Bond ◽  
Title Compound ◽  
Triple Bond ◽  
Positive Charge ◽  
Bond Distance ◽  
Double Bond Character ◽  
Acetylenic Bond ◽  
Compound C ◽  
Bond Character

The reaction of 3,3,3-tris(dimethylamino)-1-phenylprop-1-yne with bromine in pentane yields the title compound, C13H17N2 +·Br−. The acetylenic bond distance [1.197 (2) Å] is consistent with a C[triple-bond]C triple bond. The amidinium C=N bonds [1.325 (2) and 1.330 (2) Å] have double-bond character and the positive charge is delocalized between the two dimethylamino groups.

scholarly journals Morpholine-4-carboxamidinium sulfate

IUCrData ◽  
2016 ◽  
Vol 1 (1) ◽  
Author(s):  
Ioannis Tiritiris ◽  
Willi Kantlehner
Keyword(s):  
Crystal Structure ◽  
Double Bond ◽  
Hydrogen Bonds ◽  
Three Dimensional ◽  
Planar Geometry ◽  
Asymmetric Unit ◽  
Sulfate Ion ◽  
Double Bond Character ◽  
Dimensional Network ◽  
Bond Character

The asymmetric unit of the title salt, 2C5H12N3O+·SO42−, comprises two cations and one sulfate ion. In both cations, the C, N and O atoms of the morpholine rings are disordered over two sets of sites, with refined occupancies of 0.849 (3):0.151 (3) for cation I and 0.684 (4):0.316 (4) for cation II. The C—N bond lengths in both central C3N units of the carboxamidinium ions range between 1.253 (12) and 1.362 (5) Å, indicating a degree of double-bond character. The central C atoms are bonded to the three N atoms in a nearly ideal trigonal–planar geometry and the positive charges are delocalized in both CN3planes. The crystal structure is stabilized by a three-dimensional network of N—H...O hydrogen bonds between the cations and the sulfate ion. Scheme tiny font, charges and delocalized bonds almost invisible

scholarly journals Crystal structure of (1-ethoxyethylidene)dimethylazanium tetraphenylborate

2015 ◽  
Vol 71 (12) ◽  
pp. o984-o985
Author(s):  
Ioannis Tiritiris ◽  
Stefan Saur ◽  
Willi Kantlehner
Keyword(s):  
Crystal Structure ◽  
Double Bond ◽  
Bond Length ◽  
Single Bond ◽  
Charge Delocalization ◽  
Double Bond Character ◽  
Iminium Ions ◽  
Iminium Ion ◽  
Phenyl Rings ◽  
Bond Character

In the cation of the title salt, C6H14NO+·C24H20B−, the C—N bond lengths are 1.297 (2), 1.464 (2) and 1.468 (2) Å, indicating double- and single-bond character, respectively. The C—O bond length of 1.309 (2) Å shows double-bond character, pointing towards charge delocalization within the NCO plane of the iminium ion. In the crystal, C—H...π interactions between the iminium H atoms and the phenyl C atoms of the anion are present. The phenyl rings form aromatic pockets, in which the iminium ions are embedded.

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