Synthesis of heteroaryl substituted dihydrofuran and dihydropyran derivatives by green chemistry approach

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2009
Demirci, Sema
The thesis subject is mainly involved in Green Chemistry approach. Thiophene, furan and pyridine carboxaldehydes were chosen as starting compounds and vinylation and allylation with Grignard reaction afforded the corresponding racemic heteroaryl substituted allylic and homoallylic alcohols. Subsequent resolution with enzymes (PS-Amano II, Lipozym and Novazym 435) gave enantiomerically enriched alcohols with the e.e. values varied between 65 and 99%. The absolute configurations of all substrates are known. As a result of O-allylation with the common procedure formed the feasible carbon backbone for the ring closing metathesis reaction. All ring closing metathesis reactions were performed by Grubbs’ catalyst with just 5% catalyst loading. The absolute configurations of dihydrofuran and dihydropyran derivatives are known, since the chiral center configurations of all substrates are preserved throughout all the applied processes.

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Citation Formats
S. Demirci, “Synthesis of heteroaryl substituted dihydrofuran and dihydropyran derivatives by green chemistry approach,” M.S. - Master of Science, Middle East Technical University, 2009.