Hydrochloric Acid → 1-(5,5-Dimethyl-3-trifluoromethyl-4,5,6,7-tetrahydro-benzo[c]thiophen-1-yl)-ethanone

HRID 1665952Notes

Reaction equation

HRID 1665952 reaction equation
CON(C)[C:4]([C:6]1[S:7][C:8]([C:17]([F:20])([F:19])[F:18])=[C:9]2[CH2:14][C:13]([CH3:16])([CH3:15])[CH2:12][CH2:11][C:10]=12)=[O:5].[CH3:22][Li].Cl>C(OCC)C>[CH3:15][C:13]1([CH3:16])[CH2:12][CH2:11][C:10]2=[C:6]([C:4](=[O:5])[CH3:22])[S:7][C:8]([C:17]([F:20])([F:19])[F:18])=[C:9]2[CH2:14]1

Participants

5

Reactant 3

HCID 313Hydrochloric AcidHCID 598608645,5-Dimethyl-3-trifluoromethyl-4,5,6,7-tetrahydro-benzo[c]thiophene-1-carboxylic acid methoxy-methyl-amideHCID 178418348HCID 178418348, compound

Product 1

HCID 575089061-(5,5-Dimethyl-3-trifluoromethyl-4,5,6,7-tetrahydro-benzo[c]thiophen-1-yl)-ethanone

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent

Procedure

A solution of 5,5-dimethyl-3-trifluoromethyl-4,5,6,7-tetrahydro-benzo[c]thiophene-1-carboxylic acid methoxy-methyl-amide (14 g, 44 mmol) in diethyl ether (400 mL) is treated at it with methyl lithium (80 mL, 1.6 M in diethyl ether). Upon complete addition, the mixture is stirred at it for 15 min before it is poured onto water/ice and neutralized with aq. HCl. The ether phase is separated and the aq. phase is extracted two more times with diethyl ether (2×100 mL). The organic extracts are washed with brine, dried over MgSO4, filtered and evaporated. The crude product is purified by CC on silica gel eluting with heptane containing 20-30% of DCM to give 1-(5,5-dimethyl-3-trifluoromethyl-4,5,6,7-tetrahydro-benzo[c]thiophen-1-yl)-ethanone (9.1 g) as a yellow oil; LC-MS: tR=1.11 min, [M+1+CH3CN]=318.34; 1H NMR (CDCl3): δ 3.04 (t, J=7.0 Hz, 2H), 2.57 (d, J=1.2 Hz, 2H), 2.53 (s, 3H), 1.58 (t, J=7.0 Hz, 2H), 0.99 (s, 6H).

Workup

  1. additionUpon complete addition
  2. customThe ether phase is separated
  3. extractionthe aq. phase is extracted two more times with diethyl ether (2×100 mL)
  4. washThe organic extracts are washed with brine
  5. dry with materialdried over MgSO4
  6. filtrationfiltered
  7. customevaporated
  8. customThe crude product is purified by CC on silica gel eluting with heptane containing 20-30% of DCM

Sources & evidence

ORD record
ord-d8d82f88b2b94de187918c6f5c4693f5
Source dataset
uspto-grants-2011_10
Patent number
US08039644B2

Reaction notes

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