反応 #1747881

反応方程式

alcohol

(3S,4R)-4-Benzyloxycarbonylamino-3-hydroxy-5-methylhexanoic Acid Methyl Ester

2,6-lutidine

triisopropylsilyl triflate

→

13

収率 70.0%

(3S,4R)-4-Benzyloxycarbonylamino-5-methyl-3-(triisopropyl-silanyloxy)hexanoic Acid Methyl Ester

収率 70.0%

溶媒

CH2Cl2

CH2Cl2

反応条件

後処理

1. 1
   workup.WAITat room temperature for 2 h
2. 2
   その他The organic layer was separated
3. 3
   洗浄washed with 10% HCl (50 mL), NaHCO3 (50 mL, sat) and NaCl (50 mL, sat)
4. 4
   乾燥dried (Na2SO4)
5. 5
   ろ過filtered
6. 6
   濃縮concentrated
7. 7
   その他The crude oil was purified by column chromatography (silica gel, diethyl ether/hexanes 2:98 to 15:85)

実験手順

To a solution of the crude alcohol 12 (2.7 g, 9.1 mmol) in CH2Cl2 (10 mL) under argon, cooled to 0° C., 2,6-lutidine (2.6 mL, 22.7 mmol) and triisopropylsilyl triflate (3.6 mL, 13.6 mmol) were added. The reaction mixture was stirred at 0° C. for 30 min and then at room temperature for 2 h and diluted with CH2Cl2 (25 mL). The organic layer was separated and washed with 10% HCl (50 mL), NaHCO3 (50 mL, sat) and NaCl (50 mL, sat), dried (Na2SO4), filtered and concentrated. The crude oil was purified by column chromatography (silica gel, diethyl ether/hexanes 2:98 to 15:85) to yield 13 (2.9 g, 70%) as colorless oil. 1H-NMR (500 MHz, CDCl3): 0.88 (d, J=6.8 Hz, 3H), 0.92 (d, J=6.7 Hz, 3H), 1.01-1.07 (m, 2H), 1.97-2.04 (m, 1H), 2.53 (dd, J=15.3 and 4.7 Hz, 1H), 2.60 (dd, J=15.2 and 7.5 Hz, 1H), 3.57 (s, 3H), 3.59-3.65 (m, 1H), 4.34-4.40 (m, 1H), 4.78 (d, J=10.3 Hz, 1H), 5.06-5.09 (m, 2H), 7.27-7.35 (m, 5H).

出典