Tetrahydrofuran → 4-(Methanesulfinyl)-4-(methylsulfanyl)cyclopent-1-ene

Formaldehyde dimethyl mercaptal S-oxide (1.27g) was dissolved in 15 ml. of tetrahydrofuran, and 246 mg of sodium hydride was added. The mixture was stirred for 30 minutes at room temperature, and then for 2 hours at 50° C. With ice cooling, 442 mg of cis-1,4-dichloro-2-butene was added. The mixture was stirred for 1 hour with ice cooling, and then for 6.5 hours at room temperature. Methylene chloride (100 ml) was added, and the insoluble matter was separated by filtration. The filtrate was concentrated at reduced pressure, and the residue was separated by column chromatography (Florisil, eluted with methylene chloride) to afford 382 mg of 3-cyclopentenone dimethyl mercaptal S-oxide in a yield of 61%.

1. waitfor 2 hours at 50° C
2. stirringThe mixture was stirred for 1 hour with ice cooling
3. waitfor 6.5 hours at room temperature
4. customthe insoluble matter was separated by filtration
5. concentrationThe filtrate was concentrated at reduced pressure
6. customthe residue was separated by column chromatography (Florisil, eluted with methylene chloride)

ORD record

ord-fb244c2e5890411c8b3edde641ffeb48

Source dataset

uspto-grants-1977_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04020171