O. Kitagawa et al., DIASTEREOSELECTIVE IODOCARBOCYCLIZATION OF 4-PENTENYLMALONATE DERIVATIVES - APPLICATION TO CYCLOSARKOMYCIN SYNTHESIS, Tetrahedron letters, 35(7), 1994, pp. 1059-1062
The iodocarbocyclization of 4-pentenylmalonate I having a substituent
at the 2 or 3 position effectively proceeded by treating I with I-2 an
d Ti(OtBu)(4) in the presence of CuO. Stereoelectronic effect of the s
ubtituent at allylic position on diastereoselectivity was notable. As
an application of the present reaction, the efficient synthesis of cyc
losarkomycin 7 was achieved.