Synthesis of amino acid diazoketones

1986 ◽  
Vol 64 (11) ◽  
pp. 2097-2102 ◽  
Author(s):  
George R. Pettit ◽  
Paul S. Nelson
Keyword(s):  
Amino Acid ◽  
Carboxylic Acid ◽  
Acid Chloride ◽  
Low Temperatures ◽  
Oxalyl Chloride ◽  
Acyl Chloride ◽  
Carboxyl Group ◽  
Carboxylic Acid Chloride ◽  
Active Esters ◽  
Active Ester

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.

Transformation of an Acid Dipyrromethane into its Formyl Dipyrromethane without Decarboxylation

1998 ◽  
Vol 02 (04) ◽  
pp. 295-304 ◽  
Author(s):  
DENNIS H. BURNS ◽  
MICHAEL W. BURDEN ◽  
YUE HU LI
Keyword(s):  
Acid Chloride ◽  
Oxalyl Chloride ◽  
Reducing Agent ◽  
Acyl Chloride ◽  
One Pot ◽  
Sodium Triacetoxyborohydride

A method for the preparation of an α-formylated pyrrole or dipyrromethane which contains an electron-withdrawing β-acetyl is described. Formylation proceeds directly from the corresponding acid pyrrole or dipyrromethane without the need of the usual two-step acid decarboxylation/formylation procedure. The acid is first transformed into its acid chloride with oxalyl chloride, followed by reduction to the aldehyde with the mild reducing agent sodium triacetoxyborohydride, in a one-pot reaction. The non-basic acylating reagent PR 3 is necessary both for acyl chloride formation and for the reduction to succeed.

Synthesis and Reactions of Some 1H-Pyrazole-3 Carboxylic Acid Chloride

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

Transformation of the Carboxyl Group of an Amino Acid to Variously Substituted Imidazoles through a Davidson-Type Heterocyclization

Synthesis ◽  
2019 ◽  
Vol 51 (09) ◽  
pp. 1961-1968 ◽  
Author(s):  
Jim Küppers ◽  
Michaela Hympánová ◽  
Tim Keuler ◽  
Andreas Schneider ◽  
Gregor Schnakenburg ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Amino Acids ◽  
Amino Acid ◽  
Carboxylic Acid ◽  
Building Blocks ◽  
Carboxyl Group ◽  
Amino Group ◽  
Combinatorial Approach ◽  
X Ray ◽  
Imidazole Derivatives

The modification of amino acids leads to valuable building blocks for the synthesis of bioactive compounds. By keeping the amino group protected, the carboxylic acid functionality can be converted in two steps into an imidazole moiety via a Davidson-like heterocyclization. This reaction allows for a combinatorial approach, in which two positions at the heterocycle can be modified. Herein, we report the synthesis of such imidazole derivatives by employing N-protected cyclohexylalanine as the starting material. Different α-halo ketones were used and two points of diversity, positions 4 and 5, were examined. The structure of the final imidazole derivatives was confirmed by three X-ray crystal structure analyses and their protease inhibiting activities were evaluated.

scholarly journals Crystal structures of 1′-aminocobaltocenium-1-carboxylic acid chloride monohydrate and of its azo dye 1′-[2-(1-amino-2,6-dimethylphenyl)diazen-1-yl]cobaltocenium-1-carboxylic acid hexafluoridophosphate monohydrate

2019 ◽  
Vol 75 (2) ◽  
pp. 208-213 ◽  
Author(s):  
Markus Jochriem ◽  
Klaus Wurst ◽  
Holger Kopacka ◽  
Benno Bildstein
Keyword(s):  
Carboxylic Acid ◽  
Water Molecule ◽  
Functional Groups ◽  
Acid Chloride ◽  
Supramolecular Network ◽  
Carboxylic Acid Chloride ◽  
Positional Disorder ◽  
Counter Ion ◽  
Chloride Monohydrate ◽  
Hydrogen Bonded

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.

ChemInform Abstract: REACTIONS OF 2-PHENYL-4-CHLOROQUINOLINE-3-CARBOXYLIC ACID CHLORIDE

1975 ◽  
Vol 6 (12) ◽  
pp. no-no
Author(s):  
WANDA ZANKOWSKA-JASINSKA ◽  
MARIAN BALA ◽  
JAN BOKSA
Keyword(s):  
Carboxylic Acid ◽  
Acid Chloride ◽  
Carboxylic Acid Chloride
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