Scheme 1.

Synthesis of {(1R,2R,4R)-4-Methyl-1,2-cyclohexanediamine}oxalatoplatinum(II), 3a^a

^a(i) H₂O₂/HCOOH, (ii) MsCl/Py, NaN₃, (iii) Pd/CaCO₃, H₂ (3 bar), (iv) l-tartaric acid, (v) K₂PtCl₄/NaOH (0.25 M), and (vi) AgNO₃, potassium oxalate. Structures of 4-ethyl- and 4-t-butyl oxaliplatin derivatives 4 and 5, synthesized as enantiomeric mixtures (all substituents at the cyclohexane ring in equatorial positions).