Reaktion #64164

Reaktionsgleichung

4-benzoylphenylethyne

n-butyllithium

1,1,1-trifluoroacetone

diisopropylamine

→

title compound

1-(4-Benzoylphenyl)-4,4,4-trifluoro-3-hydroxy-3-methylbut-1-yne

Lösungsmittel

tetrahydrofuran

—

hexanes

tetrahydrofuran

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwas added
2. 2
   workup.ADDITIONwas added in one portion
3. 3
   Sonstigewas quenched
4. 4
   workup.ADDITIONby pouring into a saturated NH4C1 solution
5. 5
   ExtraktionThe product was extracted into diethyl ether
6. 6
   TrocknenThe combined ethers were dried
7. 7
   Sonstigeevaporated
8. 8
   Sonstigepurified by chromatography, with ethyl acetate

Vorschrift

To a cooled (-78° C.) solution of diisopropylamine (99 mL, 0.87 mmol) in freshly distilled tetrahydrofuran (5 mL) was added a solution of n-butyllithium (326 mL of a 2.5M solution in hexanes, 0.81 mmol). The solution was stirred at -78° C. for 25 minutes before a tetrahydrofuran solution of 4-benzoylphenylethyne (120 mg, 0.58 mmol) was added. The reaction was kept at -78° C. for an additional 20 minutes before 1,1,1-trifluoroacetone (521 mL, 5.8 mmol) was added in one portion. After stirring at -78° C. for 15 minutes the reaction was quenched by pouring into a saturated NH4C1 solution. The product was extracted into diethyl ether. The combined ethers were dried and evaporated. The crude product was adsorbed onto silica gel and purified by chromatography, with ethyl acetate:hexanes as the eluent (gradient 1:9 to 1:3), to yield the title compound as a white solid after trituration with hexanes (80 mg, 43%); mp 94.5°-96.0° C.; 250 MHz NMR (CDCl3): 1.76 (s,3, CH3), 2.88 (s,1, OH), 7.46-7.64 (m,5, Ar), 7.77-7.79 (m,4, Ar); MS: m/z=319(M+ 1). Analysis for C18H13F3O2 : Calculated: C, 67.92; H, 4.14; Found: C, 68.16; H, 4.15.

Quelle