Synthesis of (R)-(−) and (S)-(+)-3-(1-pyrrolyl)propyl- N-(3,5-dinitrobenzoyl)-α-phenylglycinate and derivatives. A suitable chiral polymeric phase precursor

Add time:07/26/2019    Source:sciencedirect.com

A synthetic route to obtain (R)-(−) (1), (S)-(+)-3-(1-pyrrolyl)propyl-N-(3,5-dinitrobenzoyl)-α-phenylglycinate (2) and derivatives is described. In a first step, pyrrole derivatives were prepared using the Clauson-Kaas method. The esterification, second step, was performed using basic conditions due to sensitivity of the pyrrole group toward acidic conditions. A tautomeric equilibrium involving the stereogenic center induces the product epimerization. The substitution of DMAP and Et3N by a highly hindered base, proton-sponge®, furnished the final products without racemization. The ee of 1, 2 and of the corresponding methyl esters (3 and 4) were determined by 1H NMR analysis in the presence of optically active Eu(tfc)3. Epimerization was not observed in the preparation of the carboxylate salts (5–8).

We also recommend Trading Suppliers and Manufacturers of sodium N-phenylglycinate (cas 10265-69-7). Pls Click Website Link as below: cas 10265-69-7 suppliers

Prev:Toxicity of the insecticides SPINOSAD (cas 131929-60-7) and indoxacarb to the non-target aquatic midge Chironomus riparius
Next:Synthesis of P-chiral, phosphorothioic acid analogs of N-phospholeucinamide)