反应详情

In a manner similar to Scheme I, 32 (3.80 g, 12.1 mmol) was treated with the LDA-derived anion of ethylidenecyclohexylamine (2.90 g, 23.2 mmol) in anhydrous ether. Workup and purification of the residue by HPLC using 1% Et3N in 10:1 hexanes:EtOAc as eluent provided the dieneimine (2.4 g). The imine and oxalic acid (10 g) in 40 mL H2O was heated at 100° C. for 2 h, cooled, diluted with saturated NaHCO3 and ether. The organic layer was washed with H2O and brine and dried (MgSO4). Removal of volatiles in vacuo provided 2.27 g of gum which was taken forward without further purification.

1. customWorkup and purification of the residue by HPLC
2. customEtOAc as eluent provided the dieneimine (2.4 g)
3. temperaturecooled
4. washThe organic layer was washed with H2O and brine
5. dry with materialdried (MgSO4)
6. customRemoval of volatiles in vacuo