197971-84-9

Upstream product

• 22875-82-7 2,2-diphenylpropanal 
• 143-33-9 sodium cyanide 
• 124-40-3 dimethyl amine 
• 773837-37-9 sodium cyanide 
• 5558-67-8 2,2-diphenylpropionitrile 
• 74421-26-4 2,2-diphenylpropan-1-ol 
• 40997-78-2 2,2-diphenylpropionyl chloride 
• 5558-66-7 2,2-diphenylpropanoic acid 

Downstream Products

• 197971-85-0 ethyl 2-hydroxy-3,3-diphenylbutyrate 
• 178306-50-8 (+/-)-methyl 2-hydroxy-3,3-diphenylbutanoate 
• 318472-14-9 (S)-2-(4,6-dimethylpyrimid-2-yloxy)-3,3-diphenylbutyricacid 
• 197971-87-2 2-hydroxy-3,3-diphenylbutyric acid 

Relevant academic research and scientific papers

α-hydrdroxylic acid derivatives, their production and use

The present invention relates to carboxylic acid derivatives of the formula where the radicals have the meanings stated in the description, to the preparation of these compounds and to their use as drugs.

Structural similarity and its surprises: Endothelin receptor antagonists -process research and development report

Process research and pilot plant processes are described for three endothelin (ET) receptor antagonists. The efficient synthesis of the parent compound Darusentan proceeds via a Darzens reaction from chloroacetate with benzophenone, addition of methanol to the resulting epoxide, saponification of the alkyl propionate and optical resolution of the racemic acid by crystallisation with a chiral amine. The final stage of the synthetic sequence involves the introduction of a pyrimidine moiety. Intermediates formed during this process can be used as starting materials for the synthesis of the two other ET receptor antagonists BSF 420627 and BSF 302146. An ether exchange reaction, which replaces the methoxy with a phenethyloxy substituent, enabled BSF 420627 to be prepared. The synthetic route to BSF 302146 employs trimethylaluminum to methylate the epoxide produced by the Darzens reaction.

Substituent effects on the C-C bond strength, 20 geminal substituent effects, 14: Stabilization of the cyano(dimethylamino)methyl radical - Synergistic effect due to interaction between α-amino and α-cyano groups on the radical stabilization energy

The thermolysis reactions of 3a and 2a, b were studied over a temperature range of 40°C and the activation parameters were determined. They were compared with the activation parameters of structurally comparable hydrocarbons of similar strain in order to obtain the radical stabilization enthalpies RSEs of the cyano(dimethylamino)methyl radical 1a. For this comparison the geminal interaction enthalpies of the cyano and the dimethylamino groups in the ground state had to be determined for the series of amino nitrites 4a-4c and 4j-4n by thermochemical methods. The geminal interaction in the ground state varies between -0.6 kcal/mol stabilization in 4a and a destabilization of +10.7 and +7.0 kJ mol-1 for secondary and tertiary α-dialkylaminonitriles, respectively. A synergistic (i.e. more than additive) stabilization enthalpy of 26 kJ mol-1 of la was found in contrast to predictions in the literature. This stabilization is interpreted by conjugation between the substituents, which are separated by the radical center. (Chemical Equation Presented) VCH Verlagsgesellschaft mbH, 1997.