反応 #166165

反応方程式

(trimethylsilyl)diazomethane

2,2,6,6-tetramethyl-1-(2′,4′,6′-triisopropylbiphenyl-2-yl)phosphinan-4-one

Boron trifluoride diethyl etherate

phosphine

→

title compound

収率 63.3%

2,2,7,7-Tetramethyl-1-(2′,4′,6′-triisopropylbiphenyl-2-yl)phosphepan-4-one

収率 63.3%

溶媒

hydrochloric acid

反応条件

後処理

1. 1
   その他To a 40-mL scintillation vial equipped with a magnetic stir bar
2. 2
   その他The vial was sealed with
3. 3
   その他a septa-top cap
4. 4
   その他purged with nitrogen gas for 10 minutes The solid
5. 5
   workup.DISSOLUTIONwas then dissolved with anhydrous,
6. 6
   その他degassed dichloromethane (10 mL)
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   workup.ADDITIONIn a separate 250-mL round bottom flask was added anhydrous
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   その他degassed dichloromethane (36 mL) which
9. 9
   その他was transferred by cannula to the reaction flask over the course of 3 minutes
10. 10
    workup.STIRRINGwas stirred at −78° C. for an hour
11. 11
    温度The slurry was warmed to room temperature overnight
12. 12
    workup.ADDITIONThe solution was charged into a separatory funnel
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    その他the phases were partitioned
14. 14
    その他The organic layer was collected
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    洗浄washed with aqueous saturated sodium bicarbonate (50 mL)
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    乾燥dried over sodium sulfate
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    ろ過filtered
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    濃縮concentrated in a rotary evaporator
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    その他Purification of the crude colorless oil by silica gel column chromatography on an Isco CombiFlash system (120-g column

実験手順

To a 40-mL scintillation vial equipped with a magnetic stir bar was added 2,2,6,6-tetramethyl-1-(2′,4′,6′-triisopropylbiphenyl-2-yl)phosphinan-4-one (1.38 g, 3.06 mmol, 1 equiv). The vial was sealed with a septa-top cap and then purged with nitrogen gas for 10 minutes The solid was then dissolved with anhydrous, degassed dichloromethane (10 mL). In a separate 250-mL round bottom flask was added anhydrous, degassed dichloromethane (36 mL) which was cooled to −78° C. Boron trifluoride diethyl etherate (582 μL, 4.59 mmol, 1.5 equiv) was then added to the flask. The phosphine solution was transferred by cannula to the reaction flask over the course of 3 minutes using a positive pressure of nitrogen gas. After stirring the solution for 5 minutes, (trimethylsilyl)diazomethane (2.3 mL, 4.59 mmol, 1.5 equiv, 2 Min hexane) was added slowly over 3 minutes The bright yellow solution was stirred at −78° C. for an hour, then diluted with 1 M aqueous hydrochloric acid (50 mL). The slurry was warmed to room temperature overnight. The solution was charged into a separatory funnel and the phases were partitioned. The organic layer was collected and washed with aqueous saturated sodium bicarbonate (50 mL), dried over sodium sulfate, filtered, and concentrated in a rotary evaporator. Purification of the crude colorless oil by silica gel column chromatography on an Isco CombiFlash system (120-g column; gradient: 1.5 column volumes heptane, ramp up to 98:2 heptane:methyl tert-butyl ether over 0.5 column volumes, hold at 98:2 for 2 column volumes, ramp up to 80:20 heptane:methyl tert-butyl ether over 8 column volumes, hold at 80:20 for 2 column volumes) afforded the title compound as a white solid (900 mg, 90 area % by HPLC, 63% yield). 1H NMR (400 MHz, CDCl3) δ ppm 8.00-7.90 (m, 1H), 7.43-7.29 (m, 2H), 7.28-7.21 (m, 1H), 7.00 (s, 2H), 3.10-2.86 (m, 2H), 2.73-2.37 (m, 5H), 2.34-2.18 (m, 1H), 1.95-1.77 (m, 1H), 1.31 (d, J=6.9 Hz, 5H), 1.23 (d, J=6.8 Hz, 3H), 1.20 (d, J=6.8 Hz, 3H), 1.15 (d, J=6.6 Hz, 3H), 1.10 (d, J=6.4 Hz, 3H), 1.08-1.03 (m, 4H), 1.02-0.98 (m, 4H), 0.95 (d, J=6.7 Hz, 3H). 13C NMR (100 MHz, CDCl3) δ ppm 211.3, 148.6 (d, J=35 Hz), 147.5, 145.8 (d, J=16 Hz), 136.1 (d, J=6 Hz), 135.5 (d, J=31 Hz), 134.3 (d, J=2 Hz), 132.6 (d, J=7 Hz), 127.8, 125.5, 120.1 (d, J=5 Hz), 56.5 (d, J=10 Hz), 41.5, 36.3 (d, J=10 Hz), 35.0 (d, J=24 Hz), 34.3, 33.3 (d, J=27 Hz), 32.2 (d, J=31 Hz), 31.9 (dd, J=6, 2 Hz), 30.7, 29.5 (d, J=5 Hz), 29.3 (d, J=3 Hz), 26.7 (d, J=33 Hz), 24.3 (d, J=8 Hz), 22.9 (d, J=9 Hz). 31P NMR (CDCl3, 202 MHz) δ ppm 18.3 (s). HRMS (TOF-ESI+) calcd for [M, C31H45OP]+ 464.3208. Found 464.3216.

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