3-methylbutylboronic acid

Conditions: temp:100.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 50 mL round bottom flask was charged with tert-butyl 4-(5-bromo-[1,2,4]triazolo[4,3-a]pyrazin-8-yl)piperazine-1-carboxylate (1.0 g, 2.61 mmol), isopentylboronic acid (484 mg, 4.18 mmol), Pd(PPh3)4 (300 mg, 0.261 mmol), 2 M aqueous K2CO3 (2.6 mL, 5.2 mmol) and toluene (15 mL) under N2. The resulting mixture was heated under N2 at 100° C. overnight. Work-up: the reaction mixture was filtered. The filter cake was washed with EtOAc (10 mL) and the filtrate was extracted with more EtOAc (10 mL×3). The combined organic solutions were washed with brine, dried over anhydrous Na2SO4, and concentrated in vacuo. The residue was purified by flash column chromatography on silica gel with 2% methanol in dichloromethane, to afford 0.43 g (44%) of tert-butyl 4-(5-isopentyl-[1,2,4]triazolo[4,3-a]pyrazin-8-yl)piperazine-1-carboxylate as a yellow solid. MS m/z: 375 (M+H+). the reaction mixture was filtered The filter cake was washed with EtOAc (10 mL) the filtrate was extracted with more EtOAc (10 mL×3) The combined organic solutions were washed with brine dried over anhydrous Na2SO4 concentrated in vacuo The residue was purified by flash column chromatography on silica gel with 2% methanol in dichloromethane

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 5-Isopentyl-1H-indole-2-carbaldehyde was synthesized as in Example 3.1 using 5-bromo-1H-indole-2-carbaldehyde (300 mg, 1.34 mmol) in place of 5-bromo-2-formylfuran and isopentylboronic acid (256 mg, 2.21 mmol) in place of hexylboronic acid to give 5-isopentyl-1H-indole-2-carbaldehyde (107 mg, 37%). Used without further characterization.

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 5-Isopentyl-1H-indole-2-carbaldehyde was synthesized as in Example 3.1 using 5-bromo-1H-indole-2-carbaldehyde (300 mg, 1.34 mmol) in place of 5-bromo-2-formylfuran and isopentylboronic acid (256 mg, 2.21 mmol) in place of hexylboronic acid to give 5-isopentyl-1H-indole-2-carbaldehyde (107 mg, 37%). Used without further characterization.

Conditions: temp:100.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 50 mL round bottom flask was charged with tert-butyl 4-(5-bromo-[1,2,4]triazolo[4,3-a]pyrazin-8-yl)piperazine-1-carboxylate (1.0 g, 2.61 mmol), isopentylboronic acid (484 mg, 4.18 mmol), Pd(PPh3)4 (300 mg, 0.261 mmol), 2 M aqueous K2CO3 (2.6 mL, 5.2 mmol) and toluene (15 mL) under N2. The resulting mixture was heated under N2 at 100° C. overnight. Work-up: the reaction mixture was filtered. The filter cake was washed with EtOAc (10 mL) and the filtrate was extracted with more EtOAc (10 mL×3). The combined organic solutions were washed with brine, dried over anhydrous Na2SO4, and concentrated in vacuo. The residue was purified by flash column chromatography on silica gel with 2% methanol in dichloromethane, to afford 0.43 g (44%) of tert-butyl 4-(5-isopentyl-[1,2,4]triazolo[4,3-a]pyrazin-8-yl)piperazine-1-carboxylate as a yellow solid. MS m/z: 375 (M+H+). the reaction mixture was filtered The filter cake was washed with EtOAc (10 mL) the filtrate was extracted with more EtOAc (10 mL×3) The combined organic solutions were washed with brine dried over anhydrous Na2SO4 concentrated in vacuo The residue was purified by flash column chromatography on silica gel with 2% methanol in dichloromethane

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 5-Isopentyl-1H-indole-2-carbaldehyde was synthesized as in Example 3.1 using 5-bromo-1H-indole-2-carbaldehyde (300 mg, 1.34 mmol) in place of 5-bromo-2-formylfuran and isopentylboronic acid (256 mg, 2.21 mmol) in place of hexylboronic acid to give 5-isopentyl-1H-indole-2-carbaldehyde (107 mg, 37%). Used without further characterization.