2-Methyl-2-eicosenoic acid

Methyl-2-eicosenoic acid, 38, 46 2-Methyu. nki)oi)kcanoic acid, 38,47 Methyl -cthylbenzoutc, 32, 82... 

C20H23NO5 trimethylcolchicinic acid methyl ether 3476-50-4 554.15 49.111 1,2 32450 C20H38O2 cis-11-eicosenoic acid 5561-99-9 650.00 58.467 2... 

Using chemistry developed by Tanikaga and coworkers [134], Trost [135] prepared the methyl ester of 4-hydroxy-2 -eicosenoic acid from octadecanal. The acetate of the former compound, in the presence of 0,N-bis(trimethylsilyl) acetamide and molybdenum hexacarbonyl underwent elimination, furnishing methyl 2,4-eicosadienoate as a 4 1 E,E E,Z mixture. Group transfer, by Weinreb s procedure afforded, after crystallization of the product, the corresponding pyrrolidyl amide, trichonine, 9(n=14), contaminated by some 8% of the E, Z diene isomer. The overall yield, from octadecanal, for the Trost synthesis was 28% (Scheme 6) [135]. 

Fig. 7. H NMR spectrum of eicosenoic acid methyl ester with integration of the proton signals.

The metathesis of oleochemicals in the presence of ethylene, also called ethenolysis, provides an efficient way to a-oleftns and 0)-unsaturated esters, which are useful intermediates for the synthesis of polymers, fragrances, surfactants, lubricants, and others [51, 52], The ethenolysis of methyl oleate was demonstrated in 1994 by Grubbs et al. using C3 [32], They could reach productive turnovers of 130-140. In 2001, Warwel et al. carried out the ethenolysis of the methyl esters of oleic, erucic, 5-eicosenoic, and petroselinic acids also in the presence of C3 [53]. The reactions were performed at 50°C and 10 bar using 0.025 mol% of catalyst and gave conversions from 58% to 74%. 

Fatty acid methyl esters (palmitoleic, oleic, eicosenoic and erucic acids)... 

The plate heights increase with increasing pressure in pCEC however, the plate height recorded even at 100 bar is still below what has been recorded with cHPLC. Both cHPLC and pCEC have been used to separate a mixture of methyl esters of palmitoleic, oleic, eicosenoic, and erucic acids. Capillary HPLC operating at 16 bar has separated the mixture in 110 min, whereas pCEC (16 bar and 20 kV) analyzed the mixture in 13 min. However, a better resolution has been achieved... 

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