1-iodo-2-propan-2-ylbenzene

反応条件: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: Geranyl 2-(2'-isopropylbenzoyl)benzoate (2) Magnesium (0.46 g, 19 mmol) and a crystal of iodine were placed in a dry round bottom flask which was heated to activate the magnesium. Diethyl ether was added to cover the magnesium (50mL) and several drops of 2-iodoisopropyl benzene in diethyl ether were added to start the preparation of the Grignard reagent. When the latter was underway, a solution of 2-iodoisopropyl benzene (4.18 g, 17 mnol) in diethyl ether (20 mL) was added over 20 minutes. The reaction mixture was stirred for another 15 minutes and then refluxed for 20 minutes. Phthalic anhydricie (3.11 g, 21 mmol) in toluene (50 mL) was added dropwise to the Grignard reagent at room temperature. The reaction temperature was raised to 60° C. and the diethyl ether removed by evaporation. The reaction was allowed to stir at 60° C. for 6 hours. The reaction mixture was poured on ice and 10% HCl (lOOmL) and extracted twice with diethyl ether. The organic phase was washed twice with a 10% Na2CO3 solution (200 mL). The aqueous phase was acidified with acetic acid (120 mL) and extracted twice with diethyl ether (200 mL). The organic phase was washed three times with NaHCO3 (100 mL) and then twice with water. The ether phase was dried over Na2SO4, filtered and concentrated. The yield was 1.43 g (purity: 94.6%, isolated yield: 31%) of 2-(2isopropylbenzoyl)benzoic acid. For esterification, a solution of the thus obtained acid (3.77 g, 10 mmol), geraniol (1.4 g, 9 mmol) and 4-dimethylaminopyridine (DMAP, 0.244 g, 2 mmol) in pyridine (15 mL) was prepared under anhydrous conditions. 1,3-Dicyclohexylcarbodiimide (DCC, 2.06 g, 10 mmol) was added and the reaction was stirred under a stream of nitrogen gas for 52 hours. The reaction mixture was partitioned between IM HCl and ethyl acetate. The organic extract was dried over Na2SO4, filtered and concentrated under vacuum. The ester product was purified by flash column chromatography (SiO2, 7:1 cyclohexane:ethyl acetate; isolated yield: 0.7 g, 48%) to give the following analytical data: which was heated were added refluxed for 20 minutes the diethyl ether removed by evaporation to stir at 60° C. for 6 hours The reaction mixture was poured on ice and 10% HCl (lOOmL) extracted twice with diethyl ether The organic phase was washed twice with a 10% Na2CO3 solution (200 mL) extracted twice with diethyl ether (200 mL) The organic phase was washed three times with NaHCO3 (100 mL) The ether phase was dried over Na2SO4 filtered concentrated

反応条件: temp:150.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: To a flask containing (E)-methyl 3-(4-((6-methoxybenzo[b]thiophen-3-yl)oxy)phenyl)acrylate (800 mg, 2.35 mmol) in anhydrous DMA (3.0 mL) was added 1-iodo-2-isopropylbenzene (0.751 mL, 4.70 mmol) followed by chloro[2-(dicyclohexylphosphino)-3,6-dimethoxy-2′,4′,6′-tri-1-propyl-1,1′-biphenyl][2-(2-aminoethyl)phenyl]palladium(II) (BrettPhos palladacycle 1st generation, 188 mg, 0.24 mmol), trimethylacetic acid (0.818 mL, 7.05 mmol) and potassium carbonate (974 mg, 7.05 mmol). The flask was sealed, purged and back-filled with nitrogen and the resulting mixture was heated to 150° C. for 2 h after which time the reaction was diluted with EtOAc, and washed with water and brine. The combined organic layer was dried over anhydrous MgSO4, filtered and concentrated in vacuo to give a red brown residue which was purified by column chromatography (SiO2, 0-30% EtOAc/heptane) to afford (E)-methyl 3-(4-((2-(2-isopropylphenyl)-6-methoxybenzo[b]thiophen-3-yl)oxy)phenyl)acrylate (675 mg, 1.48 mmol, 63% yield). LC/MS (m/z, MH+): 459.0. The flask was sealed purged back-filled with nitrogen was diluted with EtOAc washed with water and brine The combined organic layer was dried over anhydrous MgSO4 filtered concentrated in vacuo to give a red brown residue which was purified by column chromatography (SiO2, 0-30% EtOAc/heptane)

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: Add 1.7M tert-BuLi (26 ml, 44 mmol) dropwise, at −78° C. under inert atmosphere, to a solution of 1-Iodo-2-iso-propylbenzene (5 g, 20.3 mmol) in 70 ml of dry THF and stir. After 10 min, add Paraformaldehyde (2 g, 66.7 mmol) in a single portion. Stir the reaction at this temperature for 15 min and then at room temperature for 2 h. Add a saturated aqueous solution of NH4Cl and extract with CH2Cl2 three times. Dry the combined organic extracts over Na2SO4, filter and concentrate under reduced pressure to give a residue. Purify the residue by column chromatography on silica gel eluting with CH2Cl2 to afford pure (2-Isopropyl-phenyl)-methanol as pale purple oil. Add aqueous concentrated HBr (15 ml) to a solution of (2-Isopropyl-phenyl)-methanol (1,93 g, 12.85 mmol) in CH2Cl2(15 ml) and stir at room temperature. After 2 h. separate phases and wash the organic one with H2O; dry over Na2SO4 and evaporate at vacuum to obtain a residue. Purify the residue by column chromatography on silica gel eluting with CH2Cl2 to obtain 1-Bromomethyl-2-isopropyl-benzene as very pale pink light oil. 1H-NMR (CDCl3, 200 MHz): δ 7.33-7.25 (m, 3H), 7.19-7.11 (m, 1H), 4.58 (s, 1H), 3.31 (sep, J=6.8 Hz, 1H), 1.30 (d, J=6.8 Hz, 6H). the reaction at this temperature for 15 min at room temperature for 2 h extract with CH2Cl2 three times Dry the combined organic extracts over Na2SO4 filter concentrate under reduced pressure to give a residue Purify the residue by column chromatography on silica gel eluting with CH2Cl2

反応条件: temp:140.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: To a solution of (E)-4-(4-((6-methoxybenzo[b]thiophen-3-yl)oxy)phenyl)but-3-en-2-one (45 g, 132 mmol) in anhydrous DMA (450 mL) at room temperature was added 1-iodo-2-isopropylbenzene (57 g, 231.6 mmol), chloro[2-(dicyclohexylphosphino)-3,6-dimethoxy-2′,4′,6′-tri-i-propyl-1,1′-biphenyl][2-(2-aminoethyl)phenyl]palladium(II) (BrettPhos Palladacycle 1st generation, 6.34 g, 7.93 mmol), trimethylacetic acid (40.5 g, 397 mmol) and potassium carbonate (55 g, 397 mmol). The resulting mixture was heated at 140° C. for 1.5 hours. The reaction mixture was cooled down to 50° C. The reaction was diluted with EtOAc (400 mL) and let to cool down to room temperature. As the reaction cooled, a precipitate formed and was removed by filtration. The mother liquor was washed with water and brine, dried over anhydrous Na2SO4, filtered and concentrated in vacuo to give the crude product, which was purified by column chromatography (SiO2, 10-20% EtOAc/heptane) to afford (E)-methyl 3-(4-((2-(2-isopropylphenyl)-6-methoxybenzo[b]thiophen-3-yl)oxy)phenyl)acrylate (47 g, 102.5 mmol). 1H NMR (400 MHz, CDCl3) δ ppm=7.61 (d, J=15.9 Hz, 1H), 7.42-7.29 (m, 7H), 7.15 (ddd, J=8.1, 5.7, 2.8 Hz, 1H), 6.97 (dd, J=8.8, 2.3 Hz, 1H), 6.91-6.85 (m, 2H), 6.29 (d, J=16.0 Hz, 1H), 3.91 (s, 3H), 3.80 (s, 3H), 3.26 (p, J=6.8 Hz, 1H), 1.19 (d, J=6.9 Hz, 6H), LC/MS (m/z, MH+): 459.5. The reaction mixture was cooled down to 50° C to cool down to room temperature As the reaction cooled a precipitate formed was removed by filtration The mother liquor was washed with water and brine dried over anhydrous Na2SO4 filtered concentrated in vacuo to give the crude product, which was purified by column chromatography (SiO2, 10-20% EtOAc/heptane)

反応条件: temp:140.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: To a solution of (E)-4-(4-((6-methoxybenzo[b]thiophen-3-yl)oxy)phenyl)but-3-en-2-one (45 g, 132 mmol) in anhydrous DMA (450 mL) at room temperature was added 1-iodo-2-isopropylbenzene (57 g, 231.6 mmol), chloro[2-(dicyclohexylphosphino)-3,6-dimethoxy-2′,4′,6′-tri-i-propyl-1,1′-biphenyl][2-(2-aminoethyl)phenyl]palladium(II) (BrettPhos Palladacycle 1st generation, 6.34 g, 7.93 mmol), trimethylacetic acid (40.5 g, 397 mmol) and potassium carbonate (55 g, 397 mmol). The resulting mixture was heated at 140° C. for 1.5 hours. The reaction mixture was cooled down to 50° C. The reaction was diluted with EtOAc (400 mL) and let to cool down to room temperature. As the reaction cooled, a precipitate formed and was removed by filtration. The mother liquor was washed with water and brine, dried over anhydrous Na2SO4, filtered and concentrated in vacuo to give the crude product, which was purified by column chromatography (SiO2, 10-20% EtOAc/heptane) to afford (E)-methyl 3-(4-((2-(2-isopropylphenyl)-6-methoxybenzo[b]thiophen-3-yl)oxy)phenyl)acrylate (47 g, 102.5 mmol). 1H NMR (400 MHz, CDCl3) δ ppm=7.61 (d, J=15.9 Hz, 1H), 7.42-7.29 (m, 7H), 7.15 (ddd, J=8.1, 5.7, 2.8 Hz, 1H), 6.97 (dd, J=8.8, 2.3 Hz, 1H), 6.91-6.85 (m, 2H), 6.29 (d, J=16.0 Hz, 1H), 3.91 (s, 3H), 3.80 (s, 3H), 3.26 (p, J=6.8 Hz, 1H), 1.19 (d, J=6.9 Hz, 6H), LC/MS (m/z, MH+): 459.5. The reaction mixture was cooled down to 50° C to cool down to room temperature As the reaction cooled a precipitate formed was removed by filtration The mother liquor was washed with water and brine dried over anhydrous Na2SO4 filtered concentrated in vacuo to give the crude product, which was purified by column chromatography (SiO2, 10-20% EtOAc/heptane)

反応条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: To a 5 mL microwave vial, added a solution of (E)-4-(4-((6-methoxybenzo[b]thiophen-3-yl)oxy)phenyl)but-3-en-2-one (90 mg, 0.277 mmol) in anhydrous DMA (3.0 mL), followed by 1-iodo-2-isopropylbenzene (137 mg, 0.555 mmol), chloro[2-(dicyclohexylphosphino)-3,6-dimethoxy-2′,4′,6′-tri-i-propyl-1,1′-biphenyl][2-(2-aminoethyl)phenyl]palladium(II) (BrettPhos Palladacycle 1st generation, 22.16 mg, 0.028 mmol), trimethylacetic acid (85 mg, 0.832 mmol) and potassium carbonate (115 mg, 0.832 mmol). The microwave vial was sealed, purged and back-filled with nitrogen. The reaction mixture subjected to microwave irradiation for 2 h at 150° C. Upon completion the reaction was diluted with EtOAc, and washed with water (2×) and brine (1×). The combined organic layer was dried over anhydrous Na2SO4, filtered and concentrated in vacuo to give the crude product, which was purified by column chromatography (SiO2, 0-20% EtOAc/heptane) to afford (E)-4-(4-((2-(2-isopropylphenyl)-6-methoxybenzo[b]thiophen-3-yl)oxy)phenyl)but-3-en-2-one (71.3 mg, 0.161 mmol, 58% yield). LC/MS (m/z, MH+): 443.0. The microwave vial was sealed purged back-filled with nitrogen irradiation for 2 h at 150° C Upon completion the reaction was diluted with EtOAc washed with water (2×) and brine (1×) The combined organic layer was dried over anhydrous Na2SO4 filtered concentrated in vacuo to give the crude product, which was purified by column chromatography (SiO2, 0-20% EtOAc/heptane)

反応条件: temp:150.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: To a flask containing (E)-methyl 3-(4-((6-methoxybenzo[b]thiophen-3-yl)oxy)phenyl)acrylate (800 mg, 2.35 mmol) in anhydrous DMA (3.0 mL) was added 1-iodo-2-isopropylbenzene (0.751 mL, 4.70 mmol) followed by chloro[2-(dicyclohexylphosphino)-3,6-dimethoxy-2′,4′,6′-tri-i-propyl-1,1′-biphenyl][2-(2-aminoethyl)phenyl]palladium(II) (BrettPhos palladacycle 1st generation, 188 mg, 0.24 mmol), trimethylacetic acid (0.818 mL, 7.05 mmol) and potassium carbonate (974 mg, 7.05 mmol). The flask was sealed, purged and back-filled with nitrogen and the resulting mixture was heated to 150° C. for 2 h after which time the reaction was diluted with EtOAc, and washed with water and brine. The combined organic layer was dried over anhydrous MgSO4, filtered and concentrated in vacuo to give a red brown residue which was purified by column chromatography (SiO2, 0-30% EtOAc/heptane) to afford (E)-methyl 3-(4-((2-(2-isopropylphenyl)-6-methoxybenzo[b]thiophen-3-yl)oxy)phenyl)acrylate (675 mg, 1.48 mmol, 63% yield).). 1H NMR (400 MHz, CDCl3) δ ppm=7.61 (d, J=15.9 Hz, 1H), 7.42-7.29 (m, 7H), 7.15 (ddd, J=8.1, 5.7, 2.8 Hz, 1H), 6.97 (dd, J=8.8, 2.3 Hz, 1H), 6.91-6.85 (m, 2H), 6.29 (d, J=16.0 Hz, 1H), 3.91 (s, 3H), 3.80 (s, 3H), 3.26 (p, J=6.8 Hz, 1H), 1.19 (d, J=6.9 Hz, 6H). LC/MS (m/z, MH+): 459.0. The flask was sealed purged back-filled with nitrogen was diluted with EtOAc washed with water and brine The combined organic layer was dried over anhydrous MgSO4 filtered concentrated in vacuo to give a red brown residue which was purified by column chromatography (SiO2, 0-30% EtOAc/heptane)

反応条件: temp:60.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: Geranyl 2-(2'-isopropylbenzoyl)benzoate (2) Magnesium (0.46 g, 19 mmol) and a crystal of iodine were placed in a dry round bottom flask which was heated to activate the magnesium. Diethyl ether was added to cover the magnesium (50mL) and several drops of 2-iodoisopropyl benzene in diethyl ether were added to start the preparation of the Grignard reagent. When the latter was underway, a solution of 2-iodoisopropyl benzene (4.18 g, 17 mnol) in diethyl ether (20 mL) was added over 20 minutes. The reaction mixture was stirred for another 15 minutes and then refluxed for 20 minutes. Phthalic anhydricie (3.11 g, 21 mmol) in toluene (50 mL) was added dropwise to the Grignard reagent at room temperature. The reaction temperature was raised to 60° C. and the diethyl ether removed by evaporation. The reaction was allowed to stir at 60° C. for 6 hours. The reaction mixture was poured on ice and 10% HCl (lOOmL) and extracted twice with diethyl ether. The organic phase was washed twice with a 10% Na2CO3 solution (200 mL). The aqueous phase was acidified with acetic acid (120 mL) and extracted twice with diethyl ether (200 mL). The organic phase was washed three times with NaHCO3 (100 mL) and then twice with water. The ether phase was dried over Na2SO4, filtered and concentrated. The yield was 1.43 g (purity: 94.6%, isolated yield: 31%) of 2-(2isopropylbenzoyl)benzoic acid. For esterification, a solution of the thus obtained acid (3.77 g, 10 mmol), geraniol (1.4 g, 9 mmol) and 4-dimethylaminopyridine (DMAP, 0.244 g, 2 mmol) in pyridine (15 mL) was prepared under anhydrous conditions. 1,3-Dicyclohexylcarbodiimide (DCC, 2.06 g, 10 mmol) was added and the reaction was stirred under a stream of nitrogen gas for 52 hours. The reaction mixture was partitioned between IM HCl and ethyl acetate. The organic extract was dried over Na2SO4, filtered and concentrated under vacuum. The ester product was purified by flash column chromatography (SiO2, 7:1 cyclohexane:ethyl acetate; isolated yield: 0.7 g, 48%) to give the following analytical data: which was heated were added refluxed for 20 minutes the diethyl ether removed by evaporation to stir at 60° C. for 6 hours The reaction mixture was poured on ice and 10% HCl (lOOmL) extracted twice with diethyl ether The organic phase was washed twice with a 10% Na2CO3 solution (200 mL) extracted twice with diethyl ether (200 mL) The organic phase was washed three times with NaHCO3 (100 mL) The ether phase was dried over Na2SO4 filtered concentrated

反応条件: temp:150.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: To a flask containing (E)-methyl 3-(4-((6-methoxybenzo[b]thiophen-3-yl)oxy)phenyl)acrylate (800 mg, 2.35 mmol) in anhydrous DMA (3.0 mL) was added 1-iodo-2-isopropylbenzene (0.751 mL, 4.70 mmol) followed by chloro[2-(dicyclohexylphosphino)-3,6-dimethoxy-2′,4′,6′-tri-1-propyl-1,1′-biphenyl][2-(2-aminoethyl)phenyl]palladium(II) (BrettPhos palladacycle 1st generation, 188 mg, 0.24 mmol), trimethylacetic acid (0.818 mL, 7.05 mmol) and potassium carbonate (974 mg, 7.05 mmol). The flask was sealed, purged and back-filled with nitrogen and the resulting mixture was heated to 150° C. for 2 h after which time the reaction was diluted with EtOAc, and washed with water and brine. The combined organic layer was dried over anhydrous MgSO4, filtered and concentrated in vacuo to give a red brown residue which was purified by column chromatography (SiO2, 0-30% EtOAc/heptane) to afford (E)-methyl 3-(4-((2-(2-isopropylphenyl)-6-methoxybenzo[b]thiophen-3-yl)oxy)phenyl)acrylate (675 mg, 1.48 mmol, 63% yield). LC/MS (m/z, MH+): 459.0. The flask was sealed purged back-filled with nitrogen was diluted with EtOAc washed with water and brine The combined organic layer was dried over anhydrous MgSO4 filtered concentrated in vacuo to give a red brown residue which was purified by column chromatography (SiO2, 0-30% EtOAc/heptane)

反応条件: temp:150.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: To a flask containing (E)-methyl 3-(4-((6-methoxybenzo[b]thiophen-3-yl)oxy)phenyl)acrylate (800 mg, 2.35 mmol) in anhydrous DMA (3.0 mL) was added 1-iodo-2-isopropylbenzene (0.751 mL, 4.70 mmol) followed by chloro[2-(dicyclohexylphosphino)-3,6-dimethoxy-2′,4′,6′-tri-1-propyl-1,1′-biphenyl][2-(2-aminoethyl)phenyl]palladium(II) (BrettPhos palladacycle 1st generation, 188 mg, 0.24 mmol), trimethylacetic acid (0.818 mL, 7.05 mmol) and potassium carbonate (974 mg, 7.05 mmol). The flask was sealed, purged and back-filled with nitrogen and the resulting mixture was heated to 150° C. for 2 h after which time the reaction was diluted with EtOAc, and washed with water and brine. The combined organic layer was dried over anhydrous MgSO4, filtered and concentrated in vacuo to give a red brown residue which was purified by column chromatography (SiO2, 0-30% EtOAc/heptane) to afford (E)-methyl 3-(4-((2-(2-isopropylphenyl)-6-methoxybenzo[b]thiophen-3-yl)oxy)phenyl)acrylate (675 mg, 1.48 mmol, 63% yield). LC/MS (m/z, MH+): 459.0. The flask was sealed purged back-filled with nitrogen was diluted with EtOAc washed with water and brine The combined organic layer was dried over anhydrous MgSO4 filtered concentrated in vacuo to give a red brown residue which was purified by column chromatography (SiO2, 0-30% EtOAc/heptane)

反応条件: temp:100.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: Cu(I) iodide (38 mg, 0.2 mmol) and potassium carbonate (276 mg, 2.0 mmol) were charged into a screw-capped test tube with Teflon-lined septum. The tube was evacuated and backfilled with argon (3 cycles). tert-Amyl alcohol (2-methyl-2-butanol) (1.0 mL, bench grade solvent without degassing and pre-drying), ethylene glycol (111 μL, 2.0 mmol, bench grade solvent), 2-isopropyliodobenzene (246 mg, 1.0 mmol) and 2-isopropylbenzenethiol (90% purity, 202 μL, 1.2 mmol) were added by syringes at room temperature. The tube was heated to 100° C. and stirred for 2 4 hours. T he reaction mixture was then allowed to reach room temperature. Ethyl acetate (approx. 5 mL) and dodecane (227 μL, GC standard) were added. The aliquot was analyzed GC. The reaction mixture was then filtered and concentrated. The crude product was purified by column chromatography on silica gel using hexane as eluent to afford colorless oil as the titled product (245 mg, 91% yield). Rf=0.5 (hexane). 1H NMR (CDCl3, 300 MHz) δ 7.30 (d, 2 H, J=7.2 Hz), 7.18-7.24 (m, 2 H), 7.03-7.05 (m, 4 H), 3.50 (hept, 2 H, J=6.9 Hz), 1.25 (s, 3 H), 1.23 (s, 3 H). 13C NMR (CDCl3, 75 MHz) δ 149.2, 134.2, 132.1, 127.6, 126.7, 125.9, 30.9, 23.8. IR (neat, cm−1) 3058, 2962, 2929, 2867. MS (EI) m/z (relative intensity) 270 (100), 211 (90). HRMS (EI), Cald. for C18H22S 270.1442; Found 270.1445. The tube was evacuated T he reaction mixture to reach room temperature The reaction mixture was then filtered concentrated The crude product was purified by column chromatography on silica gel

反応条件: temp:100.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

実験手順: Cu(I) iodide (38 mg, 0.2 mmol) and potassium carbonate (276 mg, 2.0 mmol) were charged into a screw-capped test tube with Teflon-lined septum. The tube was evacuated and backfilled with argon (3 cycles). tert-Amyl alcohol (2-methyl-2-butanol) (1.0 mL, bench grade solvent without degassing and pre-drying), ethylene glycol (111 μL, 2.0 mmol, bench grade solvent), 2-isopropyliodobenzene (246 mg, 1.0 mmol) and 2-isopropylbenzenethiol (90% purity, 202 μL, 1.2 mmol) were added by syringes at room temperature. The tube was heated to 100° C. and stirred for 2 4 hours. T he reaction mixture was then allowed to reach room temperature. Ethyl acetate (approx. 5 mL) and dodecane (227 μL, GC standard) were added. The aliquot was analyzed GC. The reaction mixture was then filtered and concentrated. The crude product was purified by column chromatography on silica gel using hexane as eluent to afford colorless oil as the titled product (245 mg, 91% yield). Rf=0.5 (hexane). 1H NMR (CDCl3, 300 MHz) δ 7.30 (d, 2 H, J=7.2 Hz), 7.18-7.24 (m, 2 H), 7.03-7.05 (m, 4 H), 3.50 (hept, 2 H, J=6.9 Hz), 1.25 (s, 3 H), 1.23 (s, 3 H). 13C NMR (CDCl3, 75 MHz) δ 149.2, 134.2, 132.1, 127.6, 126.7, 125.9, 30.9, 23.8. IR (neat, cm−1) 3058, 2962, 2929, 2867. MS (EI) m/z (relative intensity) 270 (100), 211 (90). HRMS (EI), Cald. for C18H22S 270.1442; Found 270.1445. The tube was evacuated T he reaction mixture to reach room temperature The reaction mixture was then filtered concentrated The crude product was purified by column chromatography on silica gel