Chloroacetone → 1-[(4-Chlorophenyl)sulfanyl]propan-2-one
Reaction equation
Cl[CH2:2][C:3](=[O:5])[CH3:4].[Cl:6][C:7]1[CH:12]=[CH:11][C:10]([SH:13])=[CH:9][CH:8]=1>>[CH3:4][C:3]([CH2:2][S:13][C:10]1[CH:11]=[CH:12][C:7]([Cl:6])=[CH:8][CH:9]=1)=[O:5]Participants
Procedure
Reaction of chloroacetone with 4-chlorothiophenol gave (4-chlorophenyl)thiomethyl methyl ketone, which was cyclized by reaction with polyphosphoric acid to 5-chloro-3-methylbenzothiophene. Bromination of the latter compound by photochemical reaction with N-bromosuccinimide provided 5-chloro-3-bromomethylbenzothiophene, which was reacted with sodium cyanide to give 5-chloro-3-cyanomethylbenzothiophene. The latter compound was hydrolyzed and esterified to give methyl α-(5-chloro-3-benzothienyl)acetate. Reaction of the ester with sodium methoxide and n-butyl nitrite afforded methyl α-hydroxyimino-α-(5-chloro-3-benzothienyl)acetate. Reduction of the oxime by reaction with zinc and formic acid and subsequent reaction with di-tert.-butyl carbonate gave N-tert.-butoxycarbonyl-(5-chloro-3-benzothienyl)glycine. NMR (CDCl3): δ 1.1-1.5 (broad s, 9H); δ 5.4-5.7 (broad s, 1H); δ 7.2-8.0 (m, 4H).
Sources & evidence
- ORD record
- ord-d8d6c875626c41799d43f69773b06efa
- Source dataset
- uspto-grants-1985_01
- Patent number
- US04492693
Reaction notes
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