Benzaldehyde dimethyl acetal → [(4R)-5,5-Dimethyl-2-phenyl-1,3-dioxan-4-yl]methan-1-ol

HRID 1671400Notes

Reaction equation

HRID 1671400 reaction equation
[CH3:1][C:2]([CH3:9])([CH2:7][OH:8])[C@@H:3]([OH:6])[CH2:4][OH:5].[CH3:10][C:11]1[CH:16]=[CH:15][C:14](S([O-])(=O)=O)=[CH:13][CH:12]=1.C1C=C[NH+]=CC=1.COC(OC)C1C=CC=CC=1>ClCCl>[CH3:1][C:2]1([CH3:9])[CH2:7][O:8][CH:10]([C:11]2[CH:16]=[CH:15][CH:14]=[CH:13][CH:12]=2)[O:6][C@H:3]1[CH2:4][OH:5]

Participants

5

Reactant 3

HCID 62375Benzaldehyde dimethyl acetalHCID 466102Benzenesulfonic acid, 4-methyl-, compd. with pyridine (1:1)HCID 10988310(R)-3,3-dimethylbutane-1,2,4-triol

Product 1

HCID 67349301[(4R)-5,5-Dimethyl-2-phenyl-1,3-dioxan-4-yl]methan-1-olYield 220.4%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent

Procedure

Following the general procedure for the transacetalization reaction of Description 6, 6.6 g (49.2 mmol) of (2R)-3,3-dimethylbutane-1,2,4-triol (6) was reacted in 120 mL of dichloromethane (DCM) in the presence of 2.51 g (10.0 mmol) of PPTS with 11.3 mL (11.4 g, 75.0 mmol) of benzaldehyde dimethyl acetal. Purification by silica gel column chromatography using diethylether (Et2O) and hexane (Hxn) mixtures as eluent (Et2O/Hxn=2:3→Et2O/Hxn=1:1→Et2O/Hxn=3:2) provided 4.9 g (45% yield) of the title compound (7a) as a colorless liquid. Rf=0.44 (Et2O/Hxn=2:3). 1H NMR (400 MHz, CHCl3): δ=0.86 (s, 3H), 1.16 (s, 3H), 2.02-2.06 (m, 1H), 3.60-3.64 (m, 1H), 3.68-3.72 (m, 4H), 5.52 (s, 1H), 7.33-7.41 (m, 3H), 7.49-7.53 (m, 2H) ppm. MS (ESI) m/z: 223.0 (M+H)+, 245.0 (M+Na)+. The analytical data for the compound was consistent with that given in the literature.

Workup

  1. customPurification by silica gel column chromatography

Sources & evidence

ORD record
ord-26d6d2b813224fc5acc6c48b30739d7d
Source dataset
uspto-grants-2011_08
Patent number
US07994218B2

Reaction notes

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