3,3-Dimethyl-1-butyne → HCID 86700848, Verbindung

Temperatur

80 °C

A 100 ml heavy wall round bottom flask was charged with the crude intermediate 4-trifluoromethanesulfonyloxy-cyclohex-3-ene-1,1-dicarboxylic acid diethyl ester (4.0 g, 80% purity, 8.55 mmol, 1.0 equiv) from last step, PdCl2(dppf)-CH2Cl2 adduct (0.628 g, 0.769 mmol, 0.09 equiv), 4-chloro-phenylboric acid (2.67 g, 17.1 mmol, 2.0 equiv), tripotassium phosphate (4.54 g, 21.37 mmol, 2.5 equiv), ethanol (8 ml), dimethoxyethane (32.0 ml) and t-butyl acetylene (7.9 g, 97 mmol, 2.0 equiv). The flask was sealed, flushed with nitrogen for three times and stirred at 80° C. for 16 hours. After cooled at room temperature, the reaction mixture was filtered and washed with ethyl acetate (20 ml). The filtrate was concentrated under vacuum and the residue was purified by chromatography (heptanes/ethyl acetate 2/1) to give 4-(4-chloro-phenyl)-cyclohex-3-ene-1,1-dicarboxylic acid diethyl ester (2.2 g, 76%) as colorless oil. 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 1.27 (t, J=8.00 Hz, 6H) 2.29 (t, J=6.38 Hz, 2H) 2.46 (td, J=6.25, 2.02 Hz, 2H) 2.65-2.85 (m, 2H) 4.21 (q, J=8.00 Hz, 4H) 6.07 (m, 1H) 7.26 (s, 4H).

1. customThe flask was sealed
2. customflushed with nitrogen for three times
3. temperatureAfter cooled at room temperature
4. filtrationthe reaction mixture was filtered
5. washwashed with ethyl acetate (20 ml)
6. concentrationThe filtrate was concentrated under vacuum
7. customthe residue was purified by chromatography (heptanes/ethyl acetate 2/1)

ORD-Eintrag

ord-03299d46a4994367b580144cf7b2b9c1

Quelldatensatz

uspto-grants-2015_03

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08993619B2