Development of a new sterically protecting auxiliary of the metacyclophane type and application to unsymmetrical diphosphenes, 1,3-diphosphaallene and 1,4-diphosphabutatriene.
A new bulky bromobenzene of the metacyclophane type was converted to an unsymmetrically substituted 1,4-diphos-phabutatriene whose spin-spin coupling constant (3Jpp) turned out to be larger, for the first time, than the 2Jpp value of the corresponding 1,3-diphosphaallene.
Toyota
Kozo
K
Department of Chemistry, Graduate School of Science, Tohoku University, Aoba, Sendai 980-8578, Japan.
Nakamura
Akitake
A
Yoshifuji
Masaaki
M