반응 #8830

반응 방정식

tributyltin chloride

tert-butyllithium

Pyridin-4-yl-carbamic acid tert-butyl ester

ammonium chloride

→

(3-tributylstannyl-pyridin-4-yl)-carbamic acid tert-butyl ester

수율 49.0%

용매

THF

반응 조건

후처리

1. 1
   workup.ADDITIONAfter the addition
2. 2
   온도to warm to −20° C.
3. 3
   온도The reaction was cooled again to −78° C.
4. 4
   workup.WAITto reach room temperature overnight
5. 5
   추출the product extracted with dichloromethane
6. 6
   건조The combined organics were dried over magnesium sulfate
7. 7
   기타the solvent was evaporated
8. 8
   기타residue purified by flash chromatography
9. 9
   세척eluting with 20% ethyl acetate in hexanes

실험 절차

Pyridin-4-yl-carbamic acid tert-butyl ester (1.74 g, 8.95 mmol) (prepared as described in Venuti et al, J. Med. Chem. 1988, 31(11), 2136–45) dissolved in THF (150 mL) was cooled to −78° C. and a solution of 1.7M tert-butyllithium in hexanes (11.6 mL, 19.70 mmol) was added dropwise. After the addition, the stirring was continued for 1 h to −78° C. and the solution was then allowed to warm to −20° C. and stirred for an additional 3 h. The reaction was cooled again to −78° C. and tributyltin chloride (2.91 mL, 10.74 mmol) was added dropwise and the reaction was allowed to reach room temperature overnight. A saturated ammonium chloride solution was added and the product extracted with dichloromethane. The combined organics were dried over magnesium sulfate, the solvent was evaporated and residue purified by flash chromatography eluting with 20% ethyl acetate in hexanes to yield 2.12 g of (3-tributylstannyl-pyridin-4-yl)-carbamic acid tert-butyl ester.

출처