Formation and structure specifics of the SnCl4 complex with pyridine-3-carboxylic acid chloride by ab initio calculations

2017 ◽  
Vol 62 (4) ◽  
pp. 446-449
Author(s):  
V. P. Feshin ◽  
E. V. Feshina
1986 ◽  
Vol 64 (11) ◽  
pp. 2097-2102 ◽  
Author(s):  
George R. Pettit ◽  
Paul S. Nelson

A study of carboxylic acid → diazoketone conversion was pursued employing the γ-carboxyl group of otherwise protected L-glutamic acids. The Arndt–Eistert route employing carboxylic acid chloride intermediates was found best (52% yield, 5b), performed at very low temperatures employing oxalyl chloride in dimethylformamide–tetrahydrofuran followed by diazomethane at −23 °C. Alternatively, substitution of a mixed carbonic anhydride for the acyl chloride led to very similar yields (57% of 5b) of diazoketones (5). Among a series of active ester intermediates (7) examined, only the ODnp (7d) and SPfp (7f) esters were found to react (23–26% yield), at least partially, with diazomethane. The latter two reactions appear to represent the first such examples employing active esters.


2009 ◽  
Vol 15 (4) ◽  
Author(s):  
İhan Özer İlhan ◽  
Sevgi Zühal ◽  
Zülbiye Önal ◽  
Emin Saripinar

Author(s):  
Markus Jochriem ◽  
Klaus Wurst ◽  
Holger Kopacka ◽  
Benno Bildstein

1′-Aminocobaltocenium-1-carboxylic acid chloride, [Co(C5H6N)(C6H5O2)]Cl·H2O, (3), and its azo derivative 1′-[2-(1-amino-2,6-dimethylphenyl)diazen-1-yl]cobaltocenium-1-carboxylic acid hexafluoridophosphate, [Co(C13H14N3)(C6H5O2)]PF6·H2O (5) were obtained from cobaltocenium-1,1′-dicarboxylic acid hexafluoridophosphate by converting one carboxyl group to its chlorocarboxyl derivative followed by chloride/azide exchange, Curtius rearrangement, diazotiation and azo coupling with 2,6-dimethylaniline. Both title compounds crystallize as their monohydrates. In the crystal structure of 3, both functional groups lie in the same direction, with the Cp rings being nearly eclipsed, and participate in an extended hydrogen-bonded supramolecular network including the counter-ion and the water molecule of crystallization. Although the functional groups in 5 are somewhat further apart, bearing a greater torsion angle with the Cp rings now staggered, a similar supramolecular network is observed with not only the carboxylic acid and azo groups, but also with the more remote amino group participating in a hydrogen-bonded network, again including the counter-ion and the water molecule. The hexafluoridophosphate ion shows positional disorder. Compound 3 was refined as an inversion twin. In 5, each of the six F atoms is disordered over two sets of sites in a 1:1 ratio.


Sign in / Sign up

Export Citation Format

Share Document