2-[(2R)-1-羟基-4-甲基戊-2-基]异吲哚-1,3-二酮

反应条件: temp:85.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: Phthalic anhydride (10.30 g, 69.55 mmol) and D-Leucinol (8.15 g, 69.55 mmol) were mixed in THF (100 mL), the reaction mixture was heated at 85° C. and refluxed for 18 hours. After cooling to room temperature, water was added and the solution was extracted with EtOAC, the extracts were washed with 1 N HCl, water, aq. NaHCO3, water and brine, dried over MgSO4, filtered and evaporated to give 8.1 g of (R)-2-(1-hydroxy-4-methylpentan-2-yl)isoindoline-1,3-dione (47%). 1H NMR (500 MHz, CDCl3): δ 0.94 (m, 6H); 1.54 (m, 2H); 1.99 (m, 1H); 3.86 (m, 1H); 4.04 (m, 1H); 4.47 (m, 1H); 7.72 (m, 2H); 7.83 (m, 2H). refluxed for 18 hours After cooling to room temperature the solution was extracted with EtOAC the extracts were washed with 1 N HCl, water, aq. NaHCO3, water and brine dried over MgSO4 filtered evaporated

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: (R)-2-(1-hydroxy-4-methylpentan-2-yl)isoindoline-1,3-dione (example 9c) (5.88 g, 23.87 mmol) was dissolved in dry THF (25 mL) and hexamethyl-phosphoramide (30 mL) and the solution cooled to 0° C. Sodium hydride (60% in mineral oil, 1.15 g, 28.65 mmol) was added and after 10 minutes iodomethane (7.43 ml, 119.35 mmol) was added dropwise and the solution was warmed up slowly to room temperature and stirred over night. The reaction mixture was poured into ice/water, extracted with EtOAC, washed with brine, dried over MgSO4, filtered and evaporated. The residue was purified on silica gel (20% EtOAC in hexane) to give 3.92 g of (R)-2-(1-methoxy-4-methylpentan-2-yl)isoindoine-1,3-dione (63%). was added dropwise extracted with EtOAC washed with brine dried over MgSO4 filtered evaporated The residue was purified on silica gel (20% EtOAC in hexane) to give 3.92 g of (R)-2-(1-methoxy-4-methylpentan-2-yl)isoindoine-1,3-dione (63%)

反应条件: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: Nitrogen was slowly bubbled for 5 min through a suspension of 8-bromo-5H-chromeno[3,4-c]pyridine (26 mg, 0.1 mmol), (R)-2-(1-hydroxy-4-methylpentan-2-yl)isoindoline-1,3-dione (116 mg, 0.47 mmol, 4.7 equiv), 5-(di-tert-butylphosphino)-1′,3′,5′-triphenyl-17′-1,4′-bipyrazole (30 mg, 0.06 mmol, 0.6 equiv), Cs2CO3 (49 mg, 0.15 mmol, 1.5 equiv) and Pd(OAc)2 (7 mg, 0.03 mmol, 0.3 equiv) in toluene (0.5 mL) in a thick glass vial. The vial was capped and then heated at 80° C. for 19 h. The reaction mixture was cooled to ambient temperature and filtered through celite, washing with dichloromethane. The combined filtrate was concentrated under reduced pressure and the residue obtained was purified via silica gel chromatography with EtOAc:DCM (1:4) as the eluant. Fractions containing the desired product (with impurities) were concentrated under reduced pressure to give (R)-2-(1-(5H-chromeno[3,4-c]pyridin-8-yloxy)-4-methylpentan-2-yl)isoindoline-1,3-dione: 1H NMR (500 MHz, CDCl3) δ 8.54 (d, J=5.2 Hz, 1H), 8.37 (s, 1H), 7.89-7.82 (m, 2H), 7.77-7.70 (m, 2H), 7.59 (d, J=8.9 Hz, 1H), 7.41 (d, J=5.5 Hz, 1H), 6.60 (dd, J=8.7, 2.6 Hz, 1H), 6.51 (d, J=2.4 Hz, 1H), 5.12 (s, 2H), 4.85-4.75 (m, 1H), 4.57 (t, J=9.5 Hz, 1H), 4.18 (dd, J=9.5, 4.9 Hz, 1H), 2.27-2.17 (m, 1H), 1.63-1.54 (m, 2H), 1.00 (d, J=5.8 Hz, 3H), 0.97 (d, J=6.1 Hz, 3H). By proton NMR the mixture was determined to be desired product, reagent and the phosphine oxide derived from the catalyst in an approximately 10:10:3 ratio respectively. Without further purification this mixture was taken to the next step of deprotection of phthalimido group as follows: A solution of (R)-2-(1-(5H-chromeno[3,4-c]pyridin-8-yloxy)-4-methylpentan-2-yl)isoindoline-1,3-dione (44 mg, 0.102 mmol) in ethanol (2 mL) was combined with hydrazine (0.022 mL, 714 mmol) and the solution was stirred at 45° C. for 3 h. The reaction mixture was cooled to room temperature and diluted with diethylether (10 mL) then filtered. The filtrate was concentrated under reduced pressure and the residue was purified by preparative HPLC (Method A). (R)-1-(5H-chromeno[3,4-c]pyridin-8-yloxy)-4-methylpentan-2-amine (23 mg, 0.077 mmol, 43% yield for two steps) was obtained as a pale yellow oil. 1H NMR (500 MHz, CD3OD) δ 8.71-8.57 (m, 2H), 8.24 (d, J=6.4 Hz, 1H), 8.08 (m, 1H), 6.95 (dd, J=8.9, 2.4 Hz, 1H), 6.80 (d, J=2.4 Hz, 1H), 5.37 (s, 2H), 4.36 (m, 1H), 4.19 (dd, J=10.5, 6.4 Hz, 1H), 3.78-3.66 (m, 1H), 1.88-1.76 (m, 1H), 1.75-1.60 (m, 2H), 1.09-0.98 (m, 6H); LCMS (Method A) (ESI) m/e 299.2 [(M+H)+, calcd for C18H22N2O2 299.2]; optical rotation: [α]20D (MeOH)=−5.9°. The vial was capped The reaction mixture was cooled to ambient temperature filtered through celite washing with dichloromethane The combined filtrate was concentrated under reduced pressure the residue obtained was purified via silica gel chromatography with EtOAc:DCM (1:4) as the eluant Fractions containing the desired product (with impurities) were concentrated under reduced pressure

反应条件: temp:85.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: Phthalic anhydride (10.30 g, 69.55 mmol) and D-Leucinol (8.15 g, 69.55 mmol) were mixed in THF (100 mL), the reaction mixture was heated at 85° C. and refluxed for 18 hours. After cooling to room temperature, water was added and the solution was extracted with EtOAC, the extracts were washed with 1 N HCl, water, aq. NaHCO3, water and brine, dried over MgSO4, filtered and evaporated to give 8.1 g of (R)-2-(1-hydroxy-4-methylpentan-2-yl)isoindoline-1,3-dione (47%). 1H NMR (500 MHz, CDCl3): δ 0.94 (m, 6H); 1.54 (m, 2H); 1.99 (m, 1H); 3.86 (m, 1H); 4.04 (m, 1H); 4.47 (m, 1H); 7.72 (m, 2H); 7.83 (m, 2H). refluxed for 18 hours After cooling to room temperature the solution was extracted with EtOAC the extracts were washed with 1 N HCl, water, aq. NaHCO3, water and brine dried over MgSO4 filtered evaporated

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: (R)-2-(1-hydroxy-4-methylpentan-2-yl)isoindoline-1,3-dione (example 9c) (5.88 g, 23.87 mmol) was dissolved in dry THF (25 mL) and hexamethyl-phosphoramide (30 mL) and the solution cooled to 0° C. Sodium hydride (60% in mineral oil, 1.15 g, 28.65 mmol) was added and after 10 minutes iodomethane (7.43 ml, 119.35 mmol) was added dropwise and the solution was warmed up slowly to room temperature and stirred over night. The reaction mixture was poured into ice/water, extracted with EtOAC, washed with brine, dried over MgSO4, filtered and evaporated. The residue was purified on silica gel (20% EtOAC in hexane) to give 3.92 g of (R)-2-(1-methoxy-4-methylpentan-2-yl)isoindoine-1,3-dione (63%). was added dropwise extracted with EtOAC washed with brine dried over MgSO4 filtered evaporated The residue was purified on silica gel (20% EtOAC in hexane) to give 3.92 g of (R)-2-(1-methoxy-4-methylpentan-2-yl)isoindoine-1,3-dione (63%)

反应条件: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: Nitrogen was slowly bubbled for 5 min through a suspension of 8-bromo-5H-chromeno[3,4-e]pyridine (26 mg, 0.1 mmol), (R)-2-(1-hydroxy-4-methylpentan-2-yl)isoindoline-1,3-dione (116 mg, 0.47 mmol, 4.7 equiv), 5-(di-tert-butylphosphino)-1′,3′,5′-triphenyl-1′H-1,4′-bipyrazole (30 mg, 0.06 mmol, 0.6 equiv), Cs2CO3 (49 mg, 0.15 mmol, 1.5 equiv) and Pd(OAc)2 (7 mg, 0.03 mmol, 0.3 equiv) in toluene (0.5 mL) in a thick glass vial. The vial was capped and then heated at 80° C. for 19 h. The reaction mixture was cooled to ambient temperature and filtered through celite, washing with dichloromethane. The combined filtrate was concentrated under reduced pressure and the residue obtained was purified via silica gel chromatography with EtOAc:DCM (1:4) as the eluant. Fractions containing the desired product (with impurities) were concentrated under reduced pressure to give (R)-2-(1-(5H-chromeno[3,4-c]pyridin-8-yloxy)-4-methylpentan-2-yl)isoindoline-1,3-dione: 1H NMR (500 MHz, CDCl3) δ 8.54 (d, J=5.2 Hz, 1H), 8.37 (s, 1H), 7.89-7.82 (m, 2H), 7.77-7.70 (m, 2H), 7.59 (d, J=8.9 Hz, 1H), 7.41 (d, J=5.5 Hz, 1H), 6.60 (dd, J=8.7, 2.6 Hz, 1H), 6.51 (d, J=2.4 Hz, 1H), 5.12 (s, 2H), 4.85-4.75 (m, 1H), 4.57 (t, J=9.5 Hz, 1H), 4.18 (dd, J=9.5, 4.9 Hz, 1H), 2.27-2.17 (m, 1H), 1.63-1.54 (m, 2H), 1.00 (d, J=5.8 Hz, 3H), 0.97 (d, J=6.1 Hz, 3H). By proton NMR the mixture was determined to be desired product, reagent and the phosphine oxide derived from the catalyst in an approximately 10:10:3 ratio respectively. Without further purification this mixture was taken to the next step of deprotection of phthalimido group as follows: A solution of (R)-2-(1-(5H-chromeno[3,4-c]pyridin-8-yloxy)-4-methylpentan-2-yl)isoindoline-1,3-dione (44 mg, 0.102 mmol) in ethanol (2 mL) was combined with hydrazine (0.022 mL, 714 mmol) and the solution was stirred at 45° C. for 3 h. The reaction mixture was cooled to room temperature and diluted with diethylether (10 mL) then filtered. The filtrate was concentrated under reduced pressure and the residue was purified by preparative HPLC (Method A). (R)-1-(5H-chromeno[3,4-c]pyridin-8-yloxy)-4-methylpentan-2-amine (23 mg, 0.077 mmol, 43% yield for two steps) was obtained as a pale yellow oil. 1H NMR (500 MHz, CD3OD) δ 8.71-8.57 (m, 2H), 8.24 (d, J=6.4 Hz, 1H), 8.08 (m, 1H), 6.95 (dd, J=8.9, 2.4 Hz, 1H), 6.80 (d, J=2.4 Hz, 1H), 5.37 (s, 2H), 4.36 (m, 1H), 4.19 (dd, J=10.5, 6.4 Hz, 1H), 3.78-3.66 (m, 1H), 1.88-1.76 (m, 1H), 1.75-1.60 (m, 2H), 1.09-0.98 (m, 6H); LCMS (Method A) (ESI) m/e 299.2 [(M+H)+, calcd for C18H22N2O2 299.2]; optical rotation: [α]20D (MeOH)=−5.9°. The vial was capped The reaction mixture was cooled to ambient temperature filtered through celite washing with dichloromethane The combined filtrate was concentrated under reduced pressure the residue obtained was purified via silica gel chromatography with EtOAc:DCM (1:4) as the eluant Fractions containing the desired product (with impurities) were concentrated under reduced pressure

反应条件: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: Nitrogen was slowly bubbled for 5 min through a suspension of 8-bromo-5H-chromeno[3,4-e]pyridine (26 mg, 0.1 mmol), (R)-2-(1-hydroxy-4-methylpentan-2-yl)isoindoline-1,3-dione (116 mg, 0.47 mmol, 4.7 equiv), 5-(di-tert-butylphosphino)-1′,3′,5′-triphenyl-1′H-1,4′-bipyrazole (30 mg, 0.06 mmol, 0.6 equiv), Cs2CO3 (49 mg, 0.15 mmol, 1.5 equiv) and Pd(OAc)2 (7 mg, 0.03 mmol, 0.3 equiv) in toluene (0.5 mL) in a thick glass vial. The vial was capped and then heated at 80° C. for 19 h. The reaction mixture was cooled to ambient temperature and filtered through celite, washing with dichloromethane. The combined filtrate was concentrated under reduced pressure and the residue obtained was purified via silica gel chromatography with EtOAc:DCM (1:4) as the eluant. Fractions containing the desired product (with impurities) were concentrated under reduced pressure to give (R)-2-(1-(5H-chromeno[3,4-c]pyridin-8-yloxy)-4-methylpentan-2-yl)isoindoline-1,3-dione: 1H NMR (500 MHz, CDCl3) δ 8.54 (d, J=5.2 Hz, 1H), 8.37 (s, 1H), 7.89-7.82 (m, 2H), 7.77-7.70 (m, 2H), 7.59 (d, J=8.9 Hz, 1H), 7.41 (d, J=5.5 Hz, 1H), 6.60 (dd, J=8.7, 2.6 Hz, 1H), 6.51 (d, J=2.4 Hz, 1H), 5.12 (s, 2H), 4.85-4.75 (m, 1H), 4.57 (t, J=9.5 Hz, 1H), 4.18 (dd, J=9.5, 4.9 Hz, 1H), 2.27-2.17 (m, 1H), 1.63-1.54 (m, 2H), 1.00 (d, J=5.8 Hz, 3H), 0.97 (d, J=6.1 Hz, 3H). By proton NMR the mixture was determined to be desired product, reagent and the phosphine oxide derived from the catalyst in an approximately 10:10:3 ratio respectively. Without further purification this mixture was taken to the next step of deprotection of phthalimido group as follows: A solution of (R)-2-(1-(5H-chromeno[3,4-c]pyridin-8-yloxy)-4-methylpentan-2-yl)isoindoline-1,3-dione (44 mg, 0.102 mmol) in ethanol (2 mL) was combined with hydrazine (0.022 mL, 714 mmol) and the solution was stirred at 45° C. for 3 h. The reaction mixture was cooled to room temperature and diluted with diethylether (10 mL) then filtered. The filtrate was concentrated under reduced pressure and the residue was purified by preparative HPLC (Method A). (R)-1-(5H-chromeno[3,4-c]pyridin-8-yloxy)-4-methylpentan-2-amine (23 mg, 0.077 mmol, 43% yield for two steps) was obtained as a pale yellow oil. 1H NMR (500 MHz, CD3OD) δ 8.71-8.57 (m, 2H), 8.24 (d, J=6.4 Hz, 1H), 8.08 (m, 1H), 6.95 (dd, J=8.9, 2.4 Hz, 1H), 6.80 (d, J=2.4 Hz, 1H), 5.37 (s, 2H), 4.36 (m, 1H), 4.19 (dd, J=10.5, 6.4 Hz, 1H), 3.78-3.66 (m, 1H), 1.88-1.76 (m, 1H), 1.75-1.60 (m, 2H), 1.09-0.98 (m, 6H); LCMS (Method A) (ESI) m/e 299.2 [(M+H)+, calcd for C18H22N2O2 299.2]; optical rotation: [α]20D (MeOH)=−5.9°. The vial was capped The reaction mixture was cooled to ambient temperature filtered through celite washing with dichloromethane The combined filtrate was concentrated under reduced pressure the residue obtained was purified via silica gel chromatography with EtOAc:DCM (1:4) as the eluant Fractions containing the desired product (with impurities) were concentrated under reduced pressure

反应条件: temp:85.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: Phthalic anhydride (10.30 g, 69.55 mmol) and D-Leucinol (8.15 g, 69.55 mmol) were mixed in THF (100 mL), the reaction mixture was heated at 85° C. and refluxed for 18 hours. After cooling to room temperature, water was added and the solution was extracted with EtOAC, the extracts were washed with 1 N HCl, water, aq. NaHCO3, water and brine, dried over MgSO4, filtered and evaporated to give 8.1 g of (R)-2-(1-hydroxy-4-methylpentan-2-yl)isoindoline-1,3-dione (47%). 1H NMR (500 MHz, CDCl3): δ 0.94 (m, 6H); 1.54 (m, 2H); 1.99 (m, 1H); 3.86 (m, 1H); 4.04 (m, 1H); 4.47 (m, 1H); 7.72 (m, 2H); 7.83 (m, 2H). refluxed for 18 hours After cooling to room temperature the solution was extracted with EtOAC the extracts were washed with 1 N HCl, water, aq. NaHCO3, water and brine dried over MgSO4 filtered evaporated

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: (R)-2-(1-hydroxy-4-methylpentan-2-yl)isoindoline-1,3-dione (example 9c) (5.88 g, 23.87 mmol) was dissolved in dry THF (25 mL) and hexamethyl-phosphoramide (30 mL) and the solution cooled to 0° C. Sodium hydride (60% in mineral oil, 1.15 g, 28.65 mmol) was added and after 10 minutes iodomethane (7.43 ml, 119.35 mmol) was added dropwise and the solution was warmed up slowly to room temperature and stirred over night. The reaction mixture was poured into ice/water, extracted with EtOAC, washed with brine, dried over MgSO4, filtered and evaporated. The residue was purified on silica gel (20% EtOAC in hexane) to give 3.92 g of (R)-2-(1-methoxy-4-methylpentan-2-yl)isoindoine-1,3-dione (63%). was added dropwise extracted with EtOAC washed with brine dried over MgSO4 filtered evaporated The residue was purified on silica gel (20% EtOAC in hexane) to give 3.92 g of (R)-2-(1-methoxy-4-methylpentan-2-yl)isoindoine-1,3-dione (63%)

反应条件: temp:85.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: Phthalic anhydride (10.30 g, 69.55 mmol) and D-Leucinol (8.15 g, 69.55 mmol) were mixed in THF (100 mL), the reaction mixture was heated at 85° C. and refluxed for 18 hours. After cooling to room temperature, water was added and the solution was extracted with EtOAC, the extracts were washed with 1 N HCl, water, aq. NaHCO3, water and brine, dried over MgSO4, filtered and evaporated to give 8.1 g of (R)-2-(1-hydroxy-4-methylpentan-2-yl)isoindoline-1,3-dione (47%). 1H NMR (500 MHz, CDCl3): δ 0.94 (m, 6H); 1.54 (m, 2H); 1.99 (m, 1H); 3.86 (m, 1H); 4.04 (m, 1H); 4.47 (m, 1H); 7.72 (m, 2H); 7.83 (m, 2H). refluxed for 18 hours After cooling to room temperature the solution was extracted with EtOAC the extracts were washed with 1 N HCl, water, aq. NaHCO3, water and brine dried over MgSO4 filtered evaporated

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: (R)-2-(1-hydroxy-4-methylpentan-2-yl)isoindoline-1,3-dione (example 9c) (5.88 g, 23.87 mmol) was dissolved in dry THF (25 mL) and hexamethyl-phosphoramide (30 mL) and the solution cooled to 0° C. Sodium hydride (60% in mineral oil, 1.15 g, 28.65 mmol) was added and after 10 minutes iodomethane (7.43 ml, 119.35 mmol) was added dropwise and the solution was warmed up slowly to room temperature and stirred over night. The reaction mixture was poured into ice/water, extracted with EtOAC, washed with brine, dried over MgSO4, filtered and evaporated. The residue was purified on silica gel (20% EtOAC in hexane) to give 3.92 g of (R)-2-(1-methoxy-4-methylpentan-2-yl)isoindoine-1,3-dione (63%). was added dropwise extracted with EtOAC washed with brine dried over MgSO4 filtered evaporated The residue was purified on silica gel (20% EtOAC in hexane) to give 3.92 g of (R)-2-(1-methoxy-4-methylpentan-2-yl)isoindoine-1,3-dione (63%)

反应条件: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: Nitrogen was slowly bubbled for 5 min through a suspension of 8-bromo-5H-chromeno[3,4-c]pyridine (26 mg, 0.1 mmol), (R)-2-(1-hydroxy-4-methylpentan-2-yl)isoindoline-1,3-dione (116 mg, 0.47 mmol, 4.7 equiv), 5-(di-tert-butylphosphino)-1′,3′,5′-triphenyl-17′-1,4′-bipyrazole (30 mg, 0.06 mmol, 0.6 equiv), Cs2CO3 (49 mg, 0.15 mmol, 1.5 equiv) and Pd(OAc)2 (7 mg, 0.03 mmol, 0.3 equiv) in toluene (0.5 mL) in a thick glass vial. The vial was capped and then heated at 80° C. for 19 h. The reaction mixture was cooled to ambient temperature and filtered through celite, washing with dichloromethane. The combined filtrate was concentrated under reduced pressure and the residue obtained was purified via silica gel chromatography with EtOAc:DCM (1:4) as the eluant. Fractions containing the desired product (with impurities) were concentrated under reduced pressure to give (R)-2-(1-(5H-chromeno[3,4-c]pyridin-8-yloxy)-4-methylpentan-2-yl)isoindoline-1,3-dione: 1H NMR (500 MHz, CDCl3) δ 8.54 (d, J=5.2 Hz, 1H), 8.37 (s, 1H), 7.89-7.82 (m, 2H), 7.77-7.70 (m, 2H), 7.59 (d, J=8.9 Hz, 1H), 7.41 (d, J=5.5 Hz, 1H), 6.60 (dd, J=8.7, 2.6 Hz, 1H), 6.51 (d, J=2.4 Hz, 1H), 5.12 (s, 2H), 4.85-4.75 (m, 1H), 4.57 (t, J=9.5 Hz, 1H), 4.18 (dd, J=9.5, 4.9 Hz, 1H), 2.27-2.17 (m, 1H), 1.63-1.54 (m, 2H), 1.00 (d, J=5.8 Hz, 3H), 0.97 (d, J=6.1 Hz, 3H). By proton NMR the mixture was determined to be desired product, reagent and the phosphine oxide derived from the catalyst in an approximately 10:10:3 ratio respectively. Without further purification this mixture was taken to the next step of deprotection of phthalimido group as follows: A solution of (R)-2-(1-(5H-chromeno[3,4-c]pyridin-8-yloxy)-4-methylpentan-2-yl)isoindoline-1,3-dione (44 mg, 0.102 mmol) in ethanol (2 mL) was combined with hydrazine (0.022 mL, 714 mmol) and the solution was stirred at 45° C. for 3 h. The reaction mixture was cooled to room temperature and diluted with diethylether (10 mL) then filtered. The filtrate was concentrated under reduced pressure and the residue was purified by preparative HPLC (Method A). (R)-1-(5H-chromeno[3,4-c]pyridin-8-yloxy)-4-methylpentan-2-amine (23 mg, 0.077 mmol, 43% yield for two steps) was obtained as a pale yellow oil. 1H NMR (500 MHz, CD3OD) δ 8.71-8.57 (m, 2H), 8.24 (d, J=6.4 Hz, 1H), 8.08 (m, 1H), 6.95 (dd, J=8.9, 2.4 Hz, 1H), 6.80 (d, J=2.4 Hz, 1H), 5.37 (s, 2H), 4.36 (m, 1H), 4.19 (dd, J=10.5, 6.4 Hz, 1H), 3.78-3.66 (m, 1H), 1.88-1.76 (m, 1H), 1.75-1.60 (m, 2H), 1.09-0.98 (m, 6H); LCMS (Method A) (ESI) m/e 299.2 [(M+H)+, calcd for C18H22N2O2 299.2]; optical rotation: [α]20D (MeOH)=−5.9°. The vial was capped The reaction mixture was cooled to ambient temperature filtered through celite washing with dichloromethane The combined filtrate was concentrated under reduced pressure the residue obtained was purified via silica gel chromatography with EtOAc:DCM (1:4) as the eluant Fractions containing the desired product (with impurities) were concentrated under reduced pressure