Pyridine → 2-Cyano-3-thienyl acetate

HRID 1660329Notizen

Reaktionsgleichung

Reaktionsgleichung von HRID 1660329
[C:1]([C:3](=[C:8]1[CH2:12][CH2:11][S:10][CH2:9]1)[C:4]([O:6][CH3:7])=[O:5])#[N:2].S(Cl)(Cl)(=O)=O.N1C=CC=CC=1>C(Cl)Cl>[C:1]([CH:3]([C:8]1[CH:12]=[CH:11][S:10][CH:9]=1)[C:4]([O:6][CH3:7])=[O:5])#[N:2]

Komponenten

5

Edukt 3

HCID 1049PyridineHCID 24648Sulfuryl chlorideHCID 4204035HCID 4204035, Verbindung

Produkt 1

HCID 133083452-Cyano-3-thienyl acetateAusbeute 94,5 %

Reagenzien, Katalysatoren, Lösungsmittel 1

HCID 6344DichloromethaneLösungsmittel2×

Versuchsvorschrift

A solution of 5.00 g (27.3 mmol) of methyl 2-cyano-2-(3-tetrahydrothienylidene)acetate in 100 ml of methylene chloride was cooled to +5° under nitrogen and 3.70 g (27.3 mmol) of sulfuryl chloride in 5 ml of methylene chloride was added all at once. After 15 min. at +5° the solution was purged with a vigorous stream of nitrogen for 5 min. Pyridine (4.0 g, 50 mmol, 1.83 eq.) was added and the solution was brought to room temperature with a water bath. After 30 min. the reaction was quenched with 30 ml of 1 M H2SO4 and 70 ml of water. The mixture was stirred to 15 min. and the organic phase was separated. The aqueous phase was extracted with 30 ml of methylene chloride and the combined organic layers were dried by passing them through a cone of anhydrous calcium sulfate. Solvent was removed to yield an orange oil homogeneous by tlc and glc (SE-30, SP2300). Bulb to bulb distillation (about 120°/0.5 torr) yielded 4.67 g (94.5%) of methyl 2-cyano-2(3-thienyl)acetate as an analytically pure pale yellow oil, bp 108°-110°/0.5 torr, (lit. 107°-9°/0.95 torr). IR (film) 4.42 (w), 5.73 (s), 6.98 (m), 8.00 (s), 9.86 (m), 12.95 (s); NMR (CDCl3) 7.6-7.4 (m, 2H), 7.3-7.1 (d×d, J=2, 5 Hz, 1H), 5.00 (s, 1H), 3.90 (s, 3H), UV max=234 nm. 13C NMR (CDCl3) 165.0, 129.1, 127.5, 126.6, 124.7, 115.5, 53.9, 38.9.

Aufarbeitung

  1. customAfter 15 min. at +5° the solution was purged with a vigorous stream of nitrogen for 5 min
  2. customthe solution was brought to room temperature with a water bath
  3. customAfter 30 min. the reaction was quenched with 30 ml of 1 M H2SO4 and 70 ml of water
  4. customthe organic phase was separated
  5. extractionThe aqueous phase was extracted with 30 ml of methylene chloride
  6. customthe combined organic layers were dried
  7. customSolvent was removed
  8. customto yield an orange oil homogeneous by tlc and glc (SE-30, SP2300)
  9. distillationBulb to bulb distillation (about 120°/0.5 torr)

Quellen und Nachweise

ORD-Eintrag
ord-339aa4677e3e4eaea8dddd803b9cf886
Quelldatensatz
uspto-grants-1981_12
Patentnummer
US04307239

Notizen zur Reaktion

Wird geladen…