Reaktion #4589

Reaktionsgleichung

Stearoyl chloride

sodium cyanamide

charcoal

→

Stearoylcyanamide

Ausbeute 92.4%

Lösungsmittel

THF

THF

—

EtOAc petroleum ether AcOH

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwas added drop-wise
2. 2
   workup.DISTILLATIONof freshly distilled dry THF with vigorous stirring
3. 3
   SonstigeThe solids which formed
4. 4
   Filtrationwere collected by filtration
5. 5
   Filtrationfiltered
6. 6
   Sonstigeair-dried
7. 7
   Sonstigeto give 2.85 g (92.4% yield) of crude 7
8. 8
   EinengenThe filtrate was concentrated until the solution
9. 9
   workup.ADDITIONAddition of petroleum ether
10. 10
    Sonstigegave 2.29 g (crop 1) of white waxy 7
11. 11
    EinengenThe filtrate was concentrated
12. 12
    workup.ADDITIONpetroleum ether added
13. 13
    Sonstigeto give 0.28 g (crop 2) of additional product
14. 14
    Sonstigegiving a total yield of 83.3%, mp 74°-75 ° C
15. 15
    Sonstigequenching (weak)
16. 16
    Sonstigeno color reaction with ferricyanide spray reagent

Vorschrift

Stearoyl chloride (3.03 g, 0.010 mol) in 50 ml of freshly distilled dry THF was added drop-wise to a suspension of sodium cyanamide (1.92 g, 0.030 mol) in 100 ml of freshly distilled dry THF with vigorous stirring. The reaction was allowed to proceed at 25° C for 63 hours. The solids which formed were collected by filtration and the solid cake was suspended in 200 ml of distilled water. The resulting soapy suspension (pH 10.5) was acidified to pH 1.5 with 10% HCl, filtered, and air-dried to give 2.85 g (92.4% yield) of crude 7. This was dissolved in THF and the solution decolorized with activated charcoal. The filtrate was concentrated until the solution became turbid. Addition of petroleum ether gave 2.29 g (crop 1) of white waxy 7. The filtrate was concentrated and petroleum ether added to give 0.28 g (crop 2) of additional product giving a total yield of 83.3%, mp 74°-75 ° C. TLC: Rf =0.69 in EtOAc/petroleum ether/AcOH (50:100:1), detected by UV quenching (weak) and no color reaction with ferricyanide spray reagent; IR (Nujol, cm-1) 3210 (NH), 2250 (C≡N), 1735 (C=O); NMR (Silanor C, δ from TMS) 2.3-2.6 (t, --CH2 --CH2 --C=O), 1.0-1.8 (fused s, (CH2)14), 0.8-0.9 (t, CH3 --CH2 --); Anal. Calcd for C19H36N2O: C, 73.97; H, 11.76; N, 9.08. Found: C, 73.88; H, 11.50; N, 9.09.

Quelle