Reacción #320847

Ecuación de reacción

2,8-dimethyl-3-(1,3-dithian-2-ylidene)-1-oxa-8-azaspiro[4.5]decane

perchloric acid

sodium bicarbonate

→

ester

Methyl 2,8-dimethyl-1-oxa-8-azaspiro[4.5]decane-3-carboxylate

Disolventes

MeOH

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturawas heated
2. 2
   Temperaturaat reflux for 2 hours
3. 3
   Temperaturacooled
4. 4
   FiltraciónThe solids were filtered
5. 5
   Extracciónthe filtrate was extracted with methylene chloride
6. 6
   OtroThe organic extracts were dried
7. 7
   Otroevaporated
8. 8
   OtroThe residue obtained
9. 9
   Otrowas chromatographed on silica gel
10. 10
    Lavadoeluted with ammoniated 10-25% MeOH/CH2Cl2

Procedimiento

A suspension of 2,8-dimethyl-3-(1,3-dithian-2-ylidene)-1-oxa-8-azaspiro[4.5]decane (2.84 g, 9.95 mmol), HgCl2 (10.8 g, 0.04 mol) and perchloric acid (60%, 5.2 ml) in MeOH/85 ml) was heated at reflux for 2 hours, cooled and decomposed with saturated aqueous sodium bicarbonate solution. The solids were filtered and the filtrate was extracted with methylene chloride. The organic extracts were dried and evaporated. The residue obtained was chromatographed on silica gel and eluted with ammoniated 10-25% MeOH/CH2Cl2 to give the title ester as an oil (1.39 g). A 1 g sample of the oil was converted to the maleate salt in ether. The crude salt was crystallized from methylene chloride/ether to give the maleate salt of the title product (0.48 g), mp 105°-107° C.

Fuente