| Summary: | The objective of this thesis has been to synthesize an enantiopure building block of beta-blocker (S)-pindolol. This has been attempted by organic synthesis followed by lipase catalysis using candida antarctica lipase B (CALB) in kinetic resolutions. Experiments have also been performed concerning the biocatalytic hydrolysis of 9 - a possible precursor in the synthesis of vitamin K2. In the synthesis of 1-((1H-indol-4-yl)oxy)-3-chloropropan-2-ol (5) and by-product 4-(oxiran-2-ylmethoxy)-1H-indole (4) from starting material 1H-indol-4-ol (3) a yield of 52% was achieved. It was also found that by extracting with dichloromethane and washing with both water and ethyl acetate simultaneously, a high degree of purity for the products was achieved. In order to increase the yield of 5, by-product 4 was reacted with LiCl and acetic acid giving an overall yield of 59% after two steps. In the kinetic resolution of 5 using CALB in acylation an E-value of 66 was achieved, and at 53% conversion ees and eep values were at 92% and 81% respectively. However, these results are uncertain because the enantiomers of product 6 were not successfully separated in chiral HPLC, resulting in incorrect integration of peaks in HPLC chromatograms. The hydrolysis of 9 using different co-solvents and enzymes was attempted. None of the reactions performed resulted in the formation of the expected products 10, 11 and 12. In the attempted hydrolysis of 9 using CALB and ethyl acetate as co-solvent, colourless crystals were produced. MS analysis of the crystals showed a mass of 663 g/mol, which did not fit with any of the expected products. Solubility test of the crystals have been done, and the crystals were found to dissolve in water. However, NMR analysis of the crystals using D2O as solvent gave no proton or carbon peaks in 1H and 13C analysis.
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