Oxygen → Bicyclo[2.2.1]hept-2-ene, polymer with ethene

Participants

Reaction Steps

54 ml of dry oxygen-free toluene and 47 g (0.5 mol) of norbornene distilled over sodium in a stream of argon were initially introduced into a V4A steel autoclave which had been heated thoroughly in vacuo, and 6.6 ml of a 10% strength MAO solution in toluene (10 mmol) were injected. The autoclave, which was stirred with a magnetic core, was heated to 70° C. under 6 bar of ethene and, after about 15 minutes, the copolymerization was started by addition of the catalyst under pressure by means of a pressure sluice. The catalyst employed was 1×10−6 mol of [(ind)Me2PBCl2(Cp)ZrCl2] (compound 5) in 0.52 ml of toluene and 1×10−4 mol of MAO in 6.6 ml of 10% strength MAO/toluene solution, after preforming at room temperature for 15 minutes. After copolymerization at 70° C. under 6 bar of ethene for 5 hours, the mixture was cooled to RT, the autoclave was let down and the clear, viscous polymer solution was stirred slowly into 2 liters of acetone. The white polymer which had precipitated was filtered off, washed with acetone and extracted by stirring overnight in 2 liters of ethanol and 200 ml of concentrated aqueous hydrochloric acid, and the product was filtered off by means of a suction filter and rinsed with ethanol. It was then dried to constant weight at 120° C.

Provenance & Evidence