Diisopropylamine → HCID 70071026, compound

Temperature

0 °C

A solution of 0.38 ml (2.8 mmol) of diisopropylamine in 25 ml of dry tetrahydrofuran was cooled under N2 atmosphere to -78° C. and treated with 1.1 ml (2.8 mmol) of n-butyllithium. The resulting solution was warmed to 0° C. for 5 min, recooled to -78° C. and treated with a solution of 250 mg (1.34 mmol) of 1,2,3,4-tetrahydro-9H-pyrido[3,4-b]indol-1-one (J. Chem. Soc. 1960, 4699) in 5 ml of tetrahydrofuran. The solution was allowed to warm to 0° C. followed by treatment with 0.25 ml (1.4 mmol) of ethyl 2-bromohexanoate. The resulting solution was stirred at ambient temperature for 16 h, partitioned between ether and aqueous ammonium chloride, washed with saturated brine, dried over MgSO4, and concentrated. Purification of the residue by silica gel chromatography using 3:1 hexane:ethyl acetate gave 172 mg (39%) of the desired compound as a colorless oil. 1H NMR (CDCl3) δ 0.91 (br t,3H), 1.27 (5,J=7 Hz,3H), 1.4 (m,4H), 1.86 (m,1H), 2.10 (m,1H), 3.10 (m,2H), 3.66 (ddd,J=13,8,6 Hz,1H), 3.81 (ddd,13,8,6 Hz,1H), 4.2 (m,2H), 5.39 (dd,J=10,5 Hz,1H), 7.15 (td,J=7,1 Hz,1H), 7.31 (td,J=7,1 Hz,1H), 7.47 (d,J=7 Hz,1H), 7.60 (d,J=7 Hz,1H), 9.81 (br s,1H).

1. customrecooled to -78° C.
2. temperatureto warm to 0° C.
3. custompartitioned between ether and aqueous ammonium chloride
4. washwashed with saturated brine
5. dry with materialdried over MgSO4
6. concentrationconcentrated
7. customPurification of the residue by silica gel chromatography

ORD record

ord-91c66e58ba964a34a2f2b72d701485dc

Source dataset

uspto-grants-1991_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04994477