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17th July 2017 @ 18:37
Scheme:  [data]20908[/data] Compound MW(m) Mol(Mmol) Mol(M) Mass Density Volume(mL) Equiv Trimethylsilyl)diazomethane 114.2230 20.78 2.10     1.1 1.20 methanol, anhydrous 32.04       0.791 8   2-(4-chlorophenyl)-3-oxopentanenitrile 207.6570 1.75   363mg     1 (Z)-2-(4-chlorophenyl)-3-methoxypent-2-enenitrile 221.6840 1.75   388mg     1 Procedure:  6/25/17.  To a 1-neck 24/40 x 250 mL RB with stir bar and septum were added 40 mL anhydrous toluene and 8 mL anhydrous methanol with stirring under a balloon of Ar.  To this stirring, clear, colorless solution was added 1.2 mL of a 2.0 M solution of TMS-diazomethane dropwise at about 1 drop/second to give a clear, light yellow/brown solution which was stirred at RT for 5 hours. The Ar balloon was removed, and mineral oil bubbler line was connected via needle through the septum.  A clear, colorless solution of 2-(4-chlorophenyl)-3-oxopentanenitrile in 2 mL of anhydrous methanol was then added dropwise at about 1 drop/second.  N2 gas generation was evident by bubbling of the bubbler.  The resulting solution was allowed to stir at RT for 30 mins. The reaction mixture was diluted with 4 mL Et2O and 20 mL 10% ac AcOH.  The aqueous phase was extracted 3x Et2O, and the combined organic layer was washed with saturated aqueous K2CO3, dried over MgSO4. [data]20916[/data] 6/26/17 The crude product (0.807 g, 3.64 mmol, 208 %yield) was purified by column chromatography, using 10:90 EtOAc: Hexanes as the starting eluent, and then increasing to 20:80 EtOAc: Hexanes. Fractions 44-52 were collected, and the solvent was removed under reduced pressure to yield an amber-colored oil (0.110 g, 0.50 mmol, 28% yield).  [data]20918[/data]
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