| Summary: | Neste trabalho foram realizadas reações de resolução enzimática de ciano-hidrinas [(±)-mandelonitrila 1a, (±)-2-(4-clorofenil)-2-hidroxiacetonitrila 2a, (±)-2-hidroxi-2-(4- hidroxifenil)acetonitrila 3a, (±)-2-hidroxibutanonitrila 4a, (±)-2-(4- fluorofenil)acetonitrila 5a, (±)-2-hidroxi-2-(4-metoxifenil)acetonitrila 6a, (±)-2-hidroxi- 2-(3-fenoxifenil)acetonitrila 7a e (±)-(E)-2-hidroxi-4-fenilbut-3-enonitrila 8a] e de álcoois organofluorados [(±)-2,2,2-trifluoro-1-feniletanol ±9a, ±±)-1-(2,4,5- trifluorofenil)etanol 10a, (±)-1-(3-bromofenil)-2,2,2-trifluoroetanol 11a, (±)-1-(4- bromofenil)-2,2,2-trifluoroetanol 12a e (±)-1-(2-trifluorometil)feniletanol 13a] utilizando a lipase imobilizada de Candida antarctica (CALB). As reações foram realizadas em agitador orbital por um período de tempo que variou entre 24-168 h de reação apresentando diferentes conversões e excessos enantioméricos: [(R)-álcool 1a (c = 51%, ee = 51%), (S)-acetato 1b (c = 49%, ee = 98%); (R)-álcool 2a (c = 42%, ee > 99%), (S)-acetato 2b (c = 58%, ee = 94%); (R)-álcool 3a (c = 34%), (S)-acetato 3b (c = 32%, ee = 28%); (R)-álcool 4a (c = 82%), (S)-acetato 4b (c = 18%, ee = 25%); (R)-álcool 5a (c = 5%), (S)-acetato 5b (c = 55%, ee = 97%); (R)-álcool 6a (c = 44%), (S)-acetato 6b (c = 56%, ee = 99%); (R)-álcool 7a (c = 53%), (S)-acetato 7b (c = 47%, ee = 92%); (R)-álcool 8a (c = 40%), (S)-acetato 8b (c = 60%, ee = 80%); (R)-álcool 9a (c = 51%, ee = 62%), (S)- acetato 9b (c = 49%, ee > 99%); (S)-álcool 10a (c = 50%, ee > 99%), (R)-acetato 10b (c = 50%, ee > 99%); (R)-álcool 11a (c = 49%, ee = 61%), (S)-acetato 11b (c = 51%, ee = 82%); (R)-álcool 12a (c = 51%, ee = 72%), (S)-acetato 12b (c = 49%, ee > 99%); (S)-álcool 13a (c = 88%), (R)-acetato 13b (c = 12%, ee > 99). Os resultados por irradiação micro-ondas para os compostos obtidos apresentaram menores tempos de reação (1-14 h) comprovando a sua eficiência na resolução quimio-enzimática de compostos organofluorados e ciano-hidrinas: [(R)-álcool 1a (c = 60%, ee = 89%), (S)-acetato 1b (c = 40%, ee = 92%); (R)-álcool 2a (c = 47%, ee = 82%), (S)-acetato 2b (c = 53%, ee = 90%); (R)-álcool 3a (c = 34%), (S)-acetato 3b (c = 17%, ee = 59%); (R)-álcool 5a (c = 4%, ee = 88%), (S)-acetato 5b (c = 50%, ee = 92%); (R)-álcool 6a (c = 44%, ee = 73%), (S)-acetato 6b (c = 56%, ee = 90%); (R)-álcool 7a (c = 50%, ee = 84%), (S)-acetato 7b (c = 50%, ee = 84%); (R)-álcool 8a (c = 41%, ee = 91%), (S)-acetato 8b (c = 59%, ee = 74%); (S)-álcool 9a (c = 95%), (R)-acetato 9b (c = 5%, ee > 99%); (R)-álcool 10a (c = 50%, ee >99%), (S)- acetato 10b (c = 50%, ee >99%); (R)-álcool 11a (c = 58%, ee = 43%), (S)-acetato 11b (c = 42%, ee = 78%); (S)-álcool 12a (c = 51%, ee = 70%), (R)-acetato 12b (c = 49%, ee = 98%); (S)-álcool 13a (c = 85%), (R)-acetato 13b (c = 15%, ee > 99)]. Em especial destaca-se, neste trabalho o uso de células microbianas utilizando a irradiação micro-ondas na redução de fluorocetonas. Sendo assim, foi realizada reações de biorredução da (±)- 2,2,2-trifluoroacetofenona 3 em agitador orbital e irradiação micro-ondas pelo fungo marinho Mucor racemosus CBMAI 847 nas concentrações de (2,9; 5,7; 8,5 e 14 mmol/L) em pH 8 e na concentração de 14 mmol/L em pH 5. Após 6 h de reação obtiveram-se conversões entre 39-100% e excessos enantioméricos entre 74-96% em agitador orbital e por irradiação micro-ondas obteve-se uma variação de 28-64% de conversão e excesso enantiomérico entre 73-96%. Também foram realizadas reações de biorredução com as bactérias termofílicas SPZSP005, SPZSP088, SPZSP051 e SPZSP055 para cetonas organofluoradas obtendo-se elevadas enantiosseletividades (>99%) e conversões (>99%). Esse estudo relata a primeira investigação da literatura frente ao uso de fungo e bactérias termofílicas por irradiação micro-ondas aplicada em biocatálise. Foram também realizadas reações de adição de aza-Michael entre a benzilamina e cetonas ?,β-insaturadas (ciclo-hexenona, 3-metil-2-ciclo-hexen-1-ona e a 2,5-dimetil-para-benzoquinona) utilizando a CALB em diferentes solventes orgânicos (EtOAc, CH2Cl2, n-hexano, MeOH, tolueno, éter etílico e THF) em agitador orbital e por irradiação micro-ondas. Através das reações de adição de aza-Michael foi obtido por adição-1,2 e adição-1,4 como adutos iminas, os quais foram caracterizadas por espectrometria de massas. Finalmente neste trabalho aplicou a irradiação micro-ondas em biocatálise via resolução cinética, redução de cetonas e adição de Michael.
===
In this study, enzymatic kinetic resolutions of cyanohydrins [(±)-mandelonitrile 1a, (±)-2-(4-chlorophenyl)-2-hydroxyacetonitrile 2a, (±)-2-hydroxy-2-(4- hydroxyphenyl)acetonitrile 3a, (±)-2-hydroxybutanenitrile 4a, (±)-2-(4- fluorophenyl)acetonitrile 5a, (±)-2-hydroxy-2-(4-metoxiphenyl)acetonitrile 6a, (±)-2- hydroxy-2-(3-fenoxyphenyl)acetonitrile 7a and (±)-(E)-2-hydroxy-4-phenylbut-3- enonitrile 8a], and organofluorine alcohols [(±)-2,2,2-trifluoro-1-phenylethanol 9a, (±)-1-(2,4,5-trifluorophenyl)ethanol 10a, (±)-1-(3-bromophenyl)-2,2,2-trifluoroethanol 11a, (±)-1-(4-bromophenyl)-2,2,2-trifluoroethanol 12a and (±)-1-(2- trifluoromethyl)phenylethanol 13a] were performed using immobilized lipase from Candida Antarctica (CALB). The reactions were performed on an orbital shaking for a period ranging from 24 to 168 h with different conversions and enantiomeric excesses. [(R)- alcohol 1a (c = 51%, ee = 51%), (S)-acetate 1b (c = 49%, ee = 98%); (R)- alcohol 2a (c = 42%, ee > 99%), (S)-acetate 2b (c = 58%, ee = 94%); (R)-alcohol 3a (c = 34%), (S)-acetate 3b (c = 32%, ee = 28%); (R)-alcohol 4a (c = 82%), (S)-acetate 4b (c = 18%, ee = 25%); R)-alcohol 5a (c = 5%), (S)-acetate 5b (c = 55%, ee = 97%); (R)-alcohol 6a (c = 44%), (S)-acetate 6b (c = 56%, ee = 99%); (R)-alcohol 7a (c = 53%), (S)-acetate 7b (c = 47%, ee = 92%); (R)-alcohol 8a (c = 40%), (S)-acetate 8b (c = 60%, ee = 80%); (R)- alcohol 9a (c = 51%, ee = 62%), (S)-acetate 9b (c = 49%, ee > 99%); (S)-alcohol 10a (c = 50%, ee > 99%), (R)-acetate 10b (c = 50%, ee > 99%); (R)-alcohol 11a (c = 49%, ee = 61%), (S)-acetate 11b (c = 51%, ee = 82%); (R)-alcohol 12a (c = 51%, ee = 72%), (S)- acetate 12b (c = 49%, ee > 99%); (S)-alcohol 13a (c = 88%), (R)-acetate 13b (c = 12%, ee > 99). The results obtained by microwave irradiation for the substrates showed shorter reaction times (1 to 14 h) demonstrating its efficiency in chemoenzymatic esterifications of organofluorine compounds and cyanohydrins [(R)-alcohol 1a (c = 60%, ee = 89%), (S)-acetate 1b (c = 40%, ee = 92%); (R)-alcohol 2a (c = 47%, ee = 82%), (S)-acetate 2b (c = 53%, ee = 90%); (R)-alcohol 3a (c = 34%), (S)-acetate 3b (c = 17%, ee = 59%); (R)-alcohol 5a (c = 4%, ee = 88%), (S)-acetate 5b (c = 50%, ee = 92%); (R)-alcohol 6a (c = 44%, ee = 73%), (S)-acetate 6b (c = 56%, ee = 90%); (R)-alcohol 7a (c = 50%, ee = 84%), (S)-acetate 7b (c = 50%, ee = 84%); (R)-alcohol 8a (c = 41%, ee = 91%), (S)-acetate 8b (c = 59%, ee = 74%); (S)-alcohol 9a (c = 95%), (R)-acetate 9b (c = 5%, ee > 99%); (R)- alcohol 10a (c = 50%, ee >99%), (S)-acetate 10b (c = 50%, ee >99%); (R)-alcohol 11a (c = 58%, ee = 43%), (S)-acetate 11b (c = 42%, ee= 78%); (S)-alcohol 12a (c = 51%, ee = 70%), (R)-acetate 12b (c = 49%, ee = 98%); (S)-alcohol 13a (c = 85%), (R)-acetate 13b (c = 15%, ee > 99)]. In particular, this thesis show the use of microbial cells in reduction of fluoroketones by microwave irradiation. Thus, bioreduction reactions of (±)-2,2,2- trifluoroacetophenone 3 was performed in orbital shaking and microwave irradiation by marine fungus Mucor racemosus CBMAI 847 in different concentrations (2.9, 5.7, 8.5 and 14 mmol/L) at pH 8 and in the concentration of 14 mmol/L at pH 5. In the reactions after 6 h were obtained a conversion of 39 to 100% and enantiomeric excess of 74-96%, in orbital shaking. The reaction on microwave irradiation gave an increase conversion of 28-64% and enantiomeric excess of 73-96%. Bioreduction reactions were also performed with the thermophilic bacteria SPZSP005, SPZSP088, SPZSP051 and SPZSP055 for organofluorine ketones obtaining high enantioselectivities (> 99%) and conversions (> 99%). This study describes the first investigation on the literature regarding the use of thermophilic bacteria and fungus by microwave irradiation applied to biocatalysis. Were also carried out reactions of aza-Michael addition of benzylamine and ?, β-unsaturated cyclohexenones (cyclo- hexenone, 3-methyl-2-cyclo-hexen-1-one and 2,5-dimethyl-para-benzoquinone) were investigated, using CALB in different organic solvents (EtOAc, CH2Cl2, n-hexane, MeOH, toluene, ethylic ether and THF) in orbital shaking and microwave irradiation. From aza-Michael addition reactions was possible to obtain by 1,2- and 1,4-adition the adduct imines, which were characterized by mass spectrometry. Finally this thesis applied the microwave irradiation in biocatalysis via kinetic resolution, reduction of ketones and aza-Michael addition.
|
|---|
