Triethylamine → HCID 86738020, compound

Participants

Reaction Steps

To a slurry of N-(5,5-dimethyl-2-oxo-1,3,2-dioxaphosphorinan-2-yl)-1,1-dimethylethanamine (15.7 g., 70.8 mmoles) in tetrahydrofuran (50 ml.) at -5° is added over a ten minute period a solution of n-butyl lithium in hexane (46 ml. of 1.6M; 74 mmoles) with rapid stirring under dry nitrogen. This is stirred for 60 minutes at -5° and then transferred under dry nitrogen to an addition funnel and added over a 30 minute period to a solution of freshly distilled sulfur dichloride in tetrahydrofuran (25 ml.) at -5° with stirring. Stirring is continued for two hours at -5° and then filtered under dry nitrogen. The filter cake is washed with tetrahydrofuran (50 ml.) and the filtrates combined and concentrated in vacuo at ≤35°. The residue is redissolved in tetrahydrofuran (75 ml.), cooled to -5°, solid cuprous chloride (0.3 g.) added at once followed immediately by the addition of a solution of methomyl (11.5 g.; 70.8 mmoles) and triethylamine (9.8 ml., 70.8 mmoles) with stirring under dry nitrogen. About four minutes are required. Stirring is continued for two hours at -5°. The reaction mixture is then concentrated in vacuo at ≤45° and the residue taken up in methylene chloride (500 ml.) and washed with ice-water (2×300 ml.). The organic phase is vacuum filtered through celite and dried (anhydrous sodium sulfate). It is then concentrated in vacuo at ≤45° giving 28 g. of viscous oil. Preliminary absorption chromatography on silica gel using 2:1 ethyl acetate:Skellysolve B gives 15 g. of yellow oil. Chromatography of this material on silica gel using 1:4 isopropanol:Skellysolve B gives 4.4 g. (15% yld) as a white crystalline solid; MP 133.5°-134.5° (recrystallized from ethylacetate).

Provenance & Evidence