Methanol → methyl 2,3,5-tri-O-benzyl-L-xylofuranoside

HRID 638825노트

반응식

HRID 638825 반응식
[O:1]([CH3:11])[CH:2]1[O:8][C@@H:7]([CH2:9][OH:10])[C@@H:5]([OH:6])[C@@H:3]1O.[H-].[Na+].[CH2:14](Br)[C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1.[CH3:22][OH:23]>O1CCCC1.[I-].C([N+](CCCC)(CCCC)CCCC)CCC>[CH2:22]([O:23][C@H:3]1[C@H:5]([O:6][CH2:14][C:15]2[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=2)[C@H:7]([CH2:9][O:10][CH2:14][C:15]2[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=2)[O:8][CH:2]1[O:1][CH3:11])[C:15]1[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=1

참가 물질

7

반응물 4

HCID 887MethanolHCID 7498Benzyl BromideHCID 24758Sodium hydrideHCID 12042993methyl L-xylofuranoside

생성물 1

HCID 11015596methyl 2,3,5-tri-O-benzyl-L-xylofuranoside수율 87%

시약·촉매·용매 2

HCID 67553Tetrabutylammonium Iodide촉매HCID 8028Tetrahydrofuran용매

실험 절차

To an ice-cold solution of 2 (10 g, 60.9 mmol) in dry tetrahydrofuran (350 mL) was added sodium hydride (60% dispersion in mineral oil, 14.8 g, 370 mmol) and the reaction mixture was stirred for 15 min under N2. To this reaction mixture was added solid tetrabutylammonium iodide (0.36 g, 0.96 mmol) followed by a dropwise addition of benzyl bromide (36.6 g, 214 mmol). The reaction mixture was stirred for 3 days at room temperature. After the addition of methanol (25 mL) the solution was evaporated under reduced pressure, and the crude product was purified by silica gel chromatography (cyclohexane/EtOAc, 9: 1) to afford pure methyl 2,3,5-tri-O-benzyl-L-xylofuranoside (3, 23 g, 87% yield). MS 435 (M+H)+, 433 (M−H)+, 403 (M−OCH3)+; 1H NMR (CDCl3)δ 7.38-7.25 (m, 30H, aromatic H=s), 4.94 (d, 1H, H−1α, J1,2=4.3 Hz), 4.87 (d, 1H, H−1β, J,1,2 =0.9 Hz), 4.64-4.45 (m, 12H, PhCH2's), 4.37 (m, 1H, H−4α), 4.27 (dt, 1H, H−4β, J4,5a=3.7 Hz, J4,5b=6.5 Hz, J3,4=6.2 Hz), 4.17 (t, 1H, H-3α, J3,4=6.9 Hz, J2,3=5.6 Hz), 4.07 (dd, 1H, H-3β, J3,4=6.2 Hz, J2,3=2.5 Hz), 4.00 (dd, 1H, H-2α, J2,3=5.6 Hz), 3.95 (t, 1H, H-2β, J2,3=2.5 Hz), 3.70 (dd, 1H, H-5aα, J4,5a=4.5 Hz, J5a,5b=10.4 Hz), 3.66 (dd, 1H, H-5aβ, J4,5a=3.7 Hz, J5a,5b=10.7 Hz), 3.54 (dd, 1H, H-5bα, J4,5b=7.5 Hz), 3.49 (dd, 1H, H-5bβ, J4,5b=6.5 Hz).

후처리

  1. stirringThe reaction mixture was stirred for 3 days at room temperature
  2. customwas evaporated under reduced pressure
  3. customthe crude product was purified by silica gel chromatography (cyclohexane/EtOAc, 9: 1)

출처 및 근거

ORD 기록
ord-367625a709694bcfb124d79fc7c6d4d4
출처 데이터셋
uspto-grants-2010_04
특허 번호
US07691820B2

반응 노트

불러오는 중…