2,3-dimethyl maleimide (1eq)
4-penten-1-ol (1.1eq)
diethylazodicarboxylate (1.5eq)
triphenylphosphine (1.5eq)
THF (0.2M)

To a stirring solution of the maleimide and triphenylphosphine in THF at zero under nitrogen was added the alcohol in THF (10ml) and then DEAD dropwise. The reaction was allowed to warm to room temperature and then left stirring for 2.5 hrs after which time the reaction mixture was concentrated in vacuo. The resultant crude prduct was purified by flash column chromatography.

This is a good method for forming carbon nitrogen bonds. On a large scale to remove the triphenylphosphine oxide produced the crude mixture is cooled down to zero and ether added, followed by trituration. This results in a white solid which can be removed by filteration (wash with cold ether). The mother liquor is concentrated in vacuo and purified as above.

5.68-5.72 (1H, m, CH), 5.06-4.94 (2H, m, CH2), 3.49 (2H, t, CH2 J = 7.3), 1.96 (6H, s, 2 x CH3), 2.20-1.94 (2H, m, CH2), 1.69 (2H, q, CH2, J = 7.3)

Kevin I. Booker-Milburn, Christopher E. Anson, Cole Clissold, Nicola J. Costin, Richard F. Dainty, Martin Murray, Dhiren Patel, Andrew Sharpe, European Journal of Organic Chemistry, 2001, 1473-1482.