반응 #48311

반응 방정식

(R,E)-N-(2-(1-(tert-butyldimethylsilyloxy)cyclobutyl)ethylidene)-2-methylpropane-2-sulfinamide

butyllithium

2,6-difluoro-3-neopentylpyridine

N2

2,2,6,6-tetramethylpiperidine

→

N-((S)-2-(1-(tert-butyldimethylsilyloxy)cyclobutyl)-1-(2,6-difluoro-5-neopentylpyridin-3-yl)ethyl)-2-methylpropane-2-sulfinamide

수율 13.5%

용매

THF

THF

THF

반응 조건

후처리

1. 1
   workup.ADDITIONwas added dropwise
2. 2
   workup.ADDITIONAfter the addition
3. 3
   기타The reaction was then quenched with water (10 mL)
4. 4
   추출extracted with EtOAc (3×20 mL)
5. 5
   농축The combined organic layers were concentrated in vacuo
6. 6
   기타chromatographed through a Redi-Sep® pre-packed silica gel column (12 g)
7. 7
   세척eluting with 1% to 20% EtOAc in hexane

실험 절차

To a three-necked RBF was added 2,2,6,6-tetramethylpiperidine (0.34 ml, 2 mmol), THF (10 mL), and an ethanol/N2 bath. After cooling to −78° C., butyllithium (0.70 ml, 2 mmol) was added dropwise. After stirring for several minutes, the solution was cooled to −100° C. of 2,6-difluoro-3-neopentylpyridine (0.230 g, 1 mmol) in THF (2 mL) was added dropwise. The solution was then treated with (R,E)-N-(2-(1-(tert-butyldimethylsilyloxy)cyclobutyl)ethylidene)-2-methylpropane-2-sulfinamide (0.71 g, 2 mmol) in THF (3 mL). After the addition was complete the reaction was allowed to warm to 0° C. as the liquid N2 boiled off. The reaction was then quenched with water (10 mL) and extracted with EtOAc (3×20 mL). The combined organic layers were concentrated in vacuo and adsorbed onto a plug of silica gel and chromatographed through a Redi-Sep® pre-packed silica gel column (12 g), eluting with 1% to 20% EtOAc in hexane, to provide N-((S)-2-(1-(tert-butyldimethylsilyloxy)cyclobutyl)-1-(2,6-difluoro-5-neopentylpyridin-3-yl)ethyl)-2-methylpropane-2-sulfinamide (0.07 g, 11% yield). This material was used without further purification in the next step. MS m/z: 517 (M+1).

출처