HCID 54307869, compound → HCID 21292928, compound

Participants

Reaction Steps

The azetidinone sulfinyl bromide from above was dissolved in 20 ml. of methylene chloride; 0.6 ml. of stannic chloride was added to the solution. After 45 minutes at room temperature the reaction mixture was washed with water and brine, dried over anhydrous MgSO4, and evaporated in vacuo to dryness to provide 1.15 g. of methyl 7-phthalimido-3-methylenecepham-4-carboxylate-1-oxide (a mixture of R- and S-sulfoxide isomers). For the predominant isomer: nmr (CDCl3) δ3.64, 4.20 (ABq, 2, J=13.0 Hz, C2 --H), 3.84 (s, 3, COOCH3), 4.90 (d, 1, J=4.0 Hz, β-lactam H), 5.3-5.7 (m, 3), 5.97 (d, 1, J=4.0 Hz, β-lactam H), and 7.84 (bs, 4, ArH).

Provenance & Evidence