Ethyl 2-(diphenylmethyleneamino)acetate → (S)-2-(benzhydrylidene-amino)-4-methyl-hexanoic acid ethyl ester

Temperature

0 °C

A solution of (benzhydrylidene-amino)-acetic acid ethyl ester (5.48 g, 20.5 mmol) in tetrahydrofuran (40 mL) was treated with potassium t-butoxide (2.83 g, 25.26 mmol) and stirred at 0° C. for 35 min. At this time a solution of (S)-1-iodo-2-methyl-butane (5.00 g, 25.25 mmol) in tetrahydrofuran (20 mL) was added via syringe and the resulting solution stirred at 0° C. for 10 min and then room temperature overnight. The reaction mixture was concentrated in vacuo and the residue partitioned between diethyl ether and dilute aqueous hydrochloric acid. The layers were separated, and the organic layer was washed with brine and concentrated in vacuo. The residue was purified by ISCO flash chromatography (RediSep silica 120 g, 0% to 10% ethyl acetate/hexanes) which afforded (S)-2-(benzhydrylidene-amino)-4-methyl-hexanoic acid ethyl ester (5.09 g, 74%) as an oil.

1. stirringthe resulting solution stirred at 0° C. for 10 min
2. customroom temperature overnight
3. concentrationThe reaction mixture was concentrated in vacuo
4. customthe residue partitioned between diethyl ether and dilute aqueous hydrochloric acid
5. customThe layers were separated
6. washthe organic layer was washed with brine
7. concentrationconcentrated in vacuo
8. customThe residue was purified by ISCO flash chromatography (RediSep silica 120 g, 0% to 10% ethyl acetate/hexanes) which

ORD record

ord-e2b1e4a3f0e64d58bf4a398c4d0d1a9d

Source dataset

uspto-grants-2010_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07741327B2