Methylparaben → Methyl 4-hydroxycyclohexanecarboxylate

HRID 1253351Notes

Reaction equation

HRID 1253351 reaction equation
[OH:1][C:2]1[CH:11]=[CH:10][C:5]([C:6]([O:8][CH3:9])=[O:7])=[CH:4][CH:3]=1>[Rh]>[OH:1][CH:2]1[CH2:3][CH2:4][CH:5]([C:6]([O:8][CH3:9])=[O:7])[CH2:10][CH2:11]1

Participants

3

Reactant 1

HCID 7456Methylparaben

Product 1

HCID 87117Methyl 4-hydroxycyclohexanecarboxylate

Reagents, catalysts & solvents 1

HCID 23948RhodiumCatalyst

Procedure

The epoxides used as the starting materials in the general process described above can be obtained from available starting materials using an appropriate series of reactions. Thus, methyl 4-hydroxybenzoate is hydrogenated using 5% rhodium on alumina as catalyst to give methyl 4-hydroxycyclohexanecarboxylate. This is then oxidized with pyridinium chlorochromate resulting in methyl 4-oxocyclohexanecarboxylate. The 2-carbon homologation of methyl 4-oxocyclohexanecarboxylate to give methyl 4-(oxoethylidene)cyclohexanecarboxylate is carried out using the method developed by A. I. Meyers. Acetaldehyde t-butylimine is metalated with lithium diisopropylamide and then treated with diethyl chlorophosphate to provide the lithioeneaminephosphonate. Addition of methyl 4-oxocyclohexanecarboxylate and subsequent acid hydrolysis gives methyl 4-(oxoethylidene)cyclohexanecarboxylate. The reduction of this oxoethylidene compound with sodium borohydride gives methyl 4-(2-hydroxyethylidene)cyclohexanecarboxylate.

Workup

  1. customabove can be obtained

Sources & evidence

ORD record
ord-59585ad77346485397ac657969f46413
Source dataset
uspto-grants-1988_05
Patent number
US04748274

Reaction notes

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