transphobia

1. (chemistry) The preference of pairs of high-trans effect soft ligands to avoid being mutually trans by becoming cis and having other low-trans effect hard ligands trans to themselves.Examples: "This unusual reactivity and the selectivity observed can be explained as a consequence of the high transphobia of aryl and P-donor ligands […]"; "The reactions of trans-[Pt(Mef)Br(PPh₃)₂] with AgBF₄ and Ph₃ECHC(O)R (E = P, R = Me, OMe, Ph; E = As, R = Me) afford only trans-[Pt(Mef){OC(=CHEPh₃)R}(PPh₃)₂] because the C-alkyl/C-ylide transphobia is greater than the C-alkyl/O-ylide transphobia and also because of the lower steric requirement of the O-ylide ligand."; "In the symbiotic effect, a hard ligand tends to form ionic M-L bonds in which L retains more negative charge than in a soft ligand case, letting the metal ion keep more of its positive charge and hence attract additional hard ligands, […]. The antisymbiotic effect, also called transphobia, applies to pairs of high trans effect, soft ligands on a soft metal. Where a choice exists, there is a strong tendency for such ligands to avoid being mutually trans by becoming cis and preferring to have low trans effect, hard ligands trans to themselves."uncountableusually