1: phenylmethylphosphonic acid,diethyl ester With 18-crown-6 ether; sodium methylate in N,N-dimethyl-formamide T=20°C; 0.0833333 h; 2: 2-(methoxymethyloxy)-benzaldehyde With 18-crown-6 ether in N,N-dimethyl-formamide T=20 - 120°C; Horner-Emmons-Wadsworth reaction; 6 h;

1.1: NEt(i-Pr)2 / CH2Cl2 / 2 h / 25 °C 2.1: NaOMe; 18/6-crown ether / dimethylformamide / 0.08 h / 20 °C 2.2: 90 percent / 18/6-crown ether / dimethylformamide / 6 h / 20 - 120 °C View Scheme

1.1: 140 °C 2.1: NaOMe; 18/6-crown ether / dimethylformamide / 0.08 h / 20 °C 2.2: 90 percent / 18/6-crown ether / dimethylformamide / 6 h / 20 - 120 °C View Scheme

n-butyllithium in benzene T=25°C; 0.5 h; other para-substituted benzaldehydes; var. para-substituted benzyltriphenylphosphonium halides; var. temp.; Product distributionMechanism;

pyridinium p-toluenesulfonate in methanol Heating;