Hydrochloric Acid → (R)-BoroLeu-(+)-Pinanediol hydrochloride

HRID 556293Notes

Reaction equation

C[Si](C)(C)[N:3]([C@H:8]([B:13]1[O:17][C@@H:16]2[CH2:18][C@@H:19]3[CH2:22][C@H:21]([C@:15]2([CH3:25])[O:14]1)[C:20]3([CH3:24])[CH3:23])[CH2:9][CH:10]([CH3:12])[CH3:11])[Si](C)(C)C.[ClH:28]>O1CCOCC1.C(OCC)C>[ClH:28].[CH3:25][C@:15]12[C@H:21]3[CH2:22][C@H:19]([C:20]3([CH3:23])[CH3:24])[CH2:18][C@H:16]1[O:17][B:13]([C@@H:8]([NH2:3])[CH2:9][CH:10]([CH3:12])[CH3:11])[O:14]2

Participants

Conditions

Temperature: 0 °C

Procedure

To a solution of crude N,N-Bis(trimethylsilyl)-(1R)-1-[(3aS,4S,6S,7aR)-hexahydro-3a,5,5-trimethyl-4,6-methano-1,3,2-benzodioxaborol-2-yl]-3-methylbutylamine of Step 3 (79 g, 0.193 mol) in a mixture of dioxane (100 ml) and diethyl ether (200 ml), a 4 N solution of hydrogen chloride in dioxane (193 ml, 0.772 mol) was added, while cooling at 0° C. The mixture was then stirred at room temperature for 4 hours and concentrated. The residue was taken up with anhydrous hexane (500 ml) and a 2 M solution of hydrogen chloride in diethyl ether (48 ml, 0.096 mol) was added. The mixture was stirred at 0° C. for 1 hour, then concentrated. The residue was taken up with anhydrous hexane and the resulting suspension was stirred at room temperature overnight. The solid was collected by filtration and dried under vacuum affording 38.1 g of product (66% yield). A second crop (4.13 g, 7% yield) was obtained from the mother liquors.

Workup

concentrationconcentrated
stirringThe mixture was stirred at 0° C. for 1 hour
concentrationconcentrated
stirringthe resulting suspension was stirred at room temperature overnight
filtrationThe solid was collected by filtration
customdried under vacuum

Sources & evidence

ORD record: ord-967f7bcc9acb481f92042636ee6374cb
Source dataset: uspto-grants-2011_11
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US08058262B2

Reaction notes

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