3-Methoxycarbonylmethyl-2-t-butoxycarbonyl-2-(2-pentynyl)-cyclopentanol → 2-Tert-butoxycarbonyl-3-methoxycarbonylmethyl-2-(cis-2-pentenyl)-cyclopentanol

HRID 46553Notes

Reaction equation

HRID 46553 reaction equation
[CH3:1][O:2][C:3]([CH2:5][CH:6]1[CH2:10][CH2:9][CH:8]([OH:11])[C:7]1([C:17]([O:19][C:20]([CH3:23])([CH3:22])[CH3:21])=[O:18])[CH2:12][C:13]#[C:14][CH2:15][CH3:16])=[O:4].[H][H]>[Pd].CC([O-])=O.CC([O-])=O.[Pb+2].CCCCCC.CC(C)=O>[C:20]([O:19][C:17]([C:7]1([CH2:12]/[CH:13]=[CH:14]\[CH2:15][CH3:16])[CH:6]([CH2:5][C:3]([O:2][CH3:1])=[O:4])[CH2:10][CH2:9][CH:8]1[OH:11])=[O:18])([CH3:21])([CH3:23])[CH3:22]

Participants

6

Reactant 2

HCID 203875893-Methoxycarbonylmethyl-2-t-butoxycarbonyl-2-(2-pentynyl)-cyclopentanol2×HCID 178418361HCID 178418361, compound

Product 1

HCID 706014122-Tert-butoxycarbonyl-3-methoxycarbonylmethyl-2-(cis-2-pentenyl)-cyclopentanol

Reagents, catalysts & solvents 3

HCID 131709914Lindlars catalystCatalystHCID 180AcetoneSolventHCID 8058HexaneSolvent

Procedure

A 1.4 g quantity of 3-methoxycarbonylmethyl-2-methoxycarbonyl-2-(2-pentynyl)-cyclopentanol (compound (1-a)) and 2.2 g of Lindlar catalyst are dissolved in a mixture of 50 ml of n-hexane and 5 ml of acetone. The starting compound is thus reduced at room temperature and atmospheric pressure with use of hydrogen gas. The reaction is completed when the solution has absorbed the theoretical amount of the gas, whereupon the catalyst is filtered off. The filtrate is concentrated in vacuo, and the residue dissolved in benzene-ethyl acetate and purified with a silica gel column. The product is distilled in a vacuum, giving 2-methoxycarbonyl-3-methoxycarbonylmethyl-2-(cis-2-pentenyl)-cyclopentanol (compound (1-b), R1 =R2 =CH3) in a yield of 87%, b.p. 74°-78° C./0.01 mm Hg.

Workup

  1. customis thus reduced at room temperature
  2. customhas absorbed the theoretical amount of the gas
  3. filtrationwhereupon the catalyst is filtered off
  4. concentrationThe filtrate is concentrated in vacuo
  5. dissolutionthe residue dissolved in benzene-ethyl acetate
  6. custompurified with a silica gel column
  7. distillationThe product is distilled in a vacuum

Sources & evidence

ORD record
ord-3b8e5c8f9fb64a8db9a09e33c2e6039b
Source dataset
uspto-grants-1979_11
Patent number
US04173707

Reaction notes

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