Methylenecyclobutane → tert-butyl (2S,3S)-2-(tert-butyldimethylsilyloxy)-5-cyclobutylidene-1-hydroxypentan-3-ylcarbamate

HRID 1921922Notes

Reaction equation

[Si:1]([O:8][C@@H:9]([C@@H:12]([NH:16][C:17](=[O:23])[O:18][C:19]([CH3:22])([CH3:21])[CH3:20])[CH2:13][CH:14]=[CH2:15])[CH2:10][OH:11])([C:4]([CH3:7])([CH3:6])[CH3:5])([CH3:3])[CH3:2].[CH2:24]=[C:25]1CC[CH2:26]1>Cl[Ru](=C1N(C2C(C)=CC(C)=CC=2C)CCN1C1C(C)=CC(C)=CC=1C)(Cl)(=CC1C=CC=CC=1)[P](C1CCCCC1)(C1CCCCC1)C1CCCCC1.ClCCCl.CCOC(C)=O>[Si:1]([O:8][C@@H:9]([C@@H:12]([NH:16][C:17](=[O:23])[O:18][C:19]([CH3:22])([CH3:21])[CH3:20])[CH2:13][CH:14]=[C:15]1[CH2:26][CH2:25][CH2:24]1)[CH2:10][OH:11])([C:4]([CH3:7])([CH3:5])[CH3:6])([CH3:3])[CH3:2]

Participants

Conditions

Temperature: 80 °C

Procedure

A solution of tert-butyl (2S,3S)-2-(tert-butyldimethylsilyloxy)-1-hydroxyhex-5-en-3-ylcarbamate (1.0 g, 2.9 mmol) and Grubbs Catalyst 2nd generation (0.12 g, 0.14 mmol) in DCE (6 mL) was treated with methylenecyclobutane (0.79 g, 12 mmol) and heated to 80° C. in a sealed vial overnight. The reaction mixture was diluted with EtOAc, washed with saturated NaHCO3 solution, and brine. The organics were dried over MgSO4 and concentrated under reduced pressure. Purification of the crude residue by column chromatography gave tert-butyl (2S,3S)-2-(tert-butyldimethylsilyloxy)-5-cyclobutylidene-1-hydroxypentan-3-ylcarbamate (0.900 g, 81% yield) as a 2:1 mixture with starting alkene.

Workup

washwashed with saturated NaHCO3 solution, and brine
dry with materialThe organics were dried over MgSO4
concentrationconcentrated under reduced pressure
customPurification of the crude residue by column chromatography

Sources & evidence

ORD record: ord-0234e3cc27bf4b768447f0ac31d30f8a
Source dataset: uspto-grants-2012_05
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08173810B2

Reaction notes

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