Hexane → HCID 178445832, compound

Temperature

0 °C

A solution of 13.6 g of tetrabromomethane in 150 ml of methylene chloride was placed at 0° C. in a sulphonation flask under argon gasification and treated within 10 minutes with a solution of 21.51 g of triphenylphosphine in 40 ml of methylene chloride. After completion of the addition, the clear orange solution was stirred at 0° C. for a further 5 minutes and then a solution of 5.08 g of p-(trans-5-butyl-1,3-dioxan-2-yl)benzaldehyde in 30 ml of methylene chloride was added dropwise within 5 minutes. The mixture was subsequently stirred at 0° C. for a further 30 minutes, then the flask content was poured into 800 ml of hexane and the separated precipitate was filtered off (rinsing with hexane). The concentrated filtrate was digested with 400 ml of hexane, left to stand at 0° C. for 15 hours, filtered (rinsing with hexane) and the filtrate was concentrated. Low-pressure chromatography (0.5 bar) of the residue (8.2 g) on silica gel with hexane followed by petroleum ether/ethyl acetate/triethylamine (97:3:0.5) gave 3.23 g of trans-2-[p-(2,2-dibromovinyl)phenyl]-5-butyl-1,3-dioxane as colourless crystals (purity 95.1%).

1. additionAfter completion of the addition
2. stirringThe mixture was subsequently stirred at 0° C. for a further 30 minutes
3. filtrationthe separated precipitate was filtered off
4. wash(rinsing with hexane)
5. waitleft
6. waitto stand at 0° C. for 15 hours
7. filtrationfiltered
8. wash(rinsing with hexane)
9. concentrationthe filtrate was concentrated

ORD record

ord-182eff3c56b24314add3d8250cc33928

Source dataset

uspto-grants-1985_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04528114