Carbon tetrabromide → 7-(3,3-dibromo-1-pentyl-allyl)-4,4-dimethyl-3,4-dihydro-2H-quinoline-1-carboxylic acid tert-butyl ester

Temperature

0 °C

To a solution of carbon tetrabromide (0.32 g, 0.96 mmole) in 5 mL of dichloromethane, at −20° C., was added triphenyl phosphine in 5 mL of dichloromethane. After stirring at 0° C. for 15 minutes reaction mixture was treated with a solution of 7-(1-formyl-hexyl)-4,4-dimethyl-3,4-dihydro-2H-quinoline-1-carboxylic acid tert-butyl ester (0.18 g, 0.48 mmole, from Example 5 step 8) in 2 mL of dichloromethane. The reaction mixture was stirred at room temperature for 4 hours, quenched by the successive addition of 5 mL of water and 1.5 mL of saturated sodium bicarbonate. The phases were separated and aqueous phase was extracted with two 25 mL portions of dichloromethane. Organic phase was dried over MgSO4, filtered and concentrated in vacuo affording a brownish thick oil. The product was purified by flash chromatography (SiO2, 20% ethyl acetate in hexanes) to yield 0.08 g of 7-(3,3-dibromo-1-pentyl-allyl)-4,4-dimethyl-3,4-dihydro-2H-quinoline-1-carboxylic acid tert-butyl ester as a colourless oil.

1. customreaction mixture
2. stirringThe reaction mixture was stirred at room temperature for 4 hours
3. customquenched by the successive addition of 5 mL of water and 1.5 mL of saturated sodium bicarbonate
4. customThe phases were separated
5. extractionaqueous phase was extracted with two 25 mL portions of dichloromethane
6. dry with materialOrganic phase was dried over MgSO4
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customaffording a brownish thick oil
10. customThe product was purified by flash chromatography (SiO2, 20% ethyl acetate in hexanes)

ORD record

ord-c0281d92846c439e8cfac3d9b21fe11d

Source dataset

uspto-grants-2008_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07354931B2