Synthesis of 2-sulfinuul]-2-tsuklopenteen-1-ooni suntees

The asymmetric oxidation of a key intermediate for 9,11-secosterol synthesis, 2-[(4-methylphenyl)thio]-2-cyclopenten-1-one 2 with a Ti[(iPrO).sub.4]/(+)-DET/TBHP complex was studied. The kinetic resolution of racemic 2-[(4-methylphenyl)sulfinyl]-2 -cyclopenten-1-one 1 by oxidation with the same Ti-complex was also carried out. In both cases enantioenriched 2-(S)-[(4-methylphenyl)sulfinyl] -2-cyclopenten-1-one 1 was obtained in satisfactory yields and sufficient enantiomeric purity for further enantioenrichment by recrystallization. The obtained results afford simple access to the D-ring precursor of 9,11-secosterols. Keywords: asymmetric oxidation of sulfide, titanium-catalytic oxidation, enantiomeric sulfoxide, 9,11-secosterols. Uuriti 9,11-sekosterooli sunteesi peamise lahteuhendi 2-(S)-[(4-metuulfenuul)sulfinuul]-2-tsuklopenteen-1-ooni 1 saamisvoimalusi 2-[(4-metuulfenuul)tio]-2-tsuklopenteen-1-ooni 2 asummeetrilisel oksudatsioonil ja rac-2-[(4-metuulfenuul)sulfinuul]-2-tsuklopenteen-1-ooni 1 kineetilisel lahutamisel, kasutades vahendina asummeetrilist Sharplessi Ti[(iPrO).sub.4]/(+)-DET/TBHP kompleksi. Molemal juhul saadi piisava enantioselektiivsusega 2-(S)-[(4-metuulfenuul)sulfinuul]-2-tsuklopenteen-1-oon 1 nii, et edasine enantiomeerne rikastamine oli voimalik umberkristallimise teel. Saadud tulemused tagavad lihtsa voimaluse 9,11-sekosterooli D-ringi eellase saamiseks ja avavad tee sekosteroolide taiskeemiliseks sunteesiks.