Selective synthesis of conformationally restricted mono-cyclopentadienyl titanium(iv) complexes of p-tBu-calix[6]arene

Abstract

Reaction of p-'Bu-calix[6]arene with potassium metal in methanol followed by [TiCp2Cl2] affords novel mononuclear and binuclear monocyclopentadienyl titanium(IV) complexes, both having the same inverted double cone conformation with a Cp in one of the cavities, in both complexes.

Calixarenes as platforms for the construction of multimetallic complexes

“…From a coordination chemistry perspective, calix [6]arene macrocycles have great potential in the design of new complexes containing several metal centres. Nevertheless, there is a dearth of structural information on how this calixarene binds to metal centres coupled with limited synthetic methodologies to prepare the metal complexes [22][23][24][25][26][27].…”

“…Reflux hexane [1] ð2Þ aluminium(III) centres are coordinatively satisfied by different levels of methyl and phenolate moieties. Controlled sequential multi-metallation of calix [6]arene is possible by selective preparation of mono-titanium(IV) and di-titanium(IV) complexes, Scheme 4 [26]. Metallation of the three phenolic groups in the mono-titanium complex offers scope for incorporating other metals.…”

Induced‐Fit Encapsulation by a 1,3,5‐Alternate Calix[6]arene

“…[8] However, seven other conformations, which differ in the syn or anti orientations of the aromatic units with respect to one another, are theoretically possible. [9] While the partial cone, [10] 1,2-alternate, [11] 1,3-alternate, [12] 1,4-alternate, [13] and 1,2,3-alternate [14] conformations are known, the 1,2,4-alternate and 1,3,5-alternate conformations have not been reported to date. The 1,3,5-alternate conformation is particularly attractive since it should display a highly symmetrical closed cavity and could constitute a useful platform for the introduction of two divergent functional domains in a spatially controlled manner.…”

2 ? 1 Ba/Ti(iv) Heterobimetallic complex based on two calix[6]arenes

“…12,13 The calix [6]arenes are in the 1,3-alternate conformation, as in recently authenticated monocyclopentadienyltitanium(IV) complexes of the same calixarene. 14 The symmetry of the molecule imposes a linear arrangement of the three metal centres, so that the cavities devoid of metal ions are pointing in opposite directions. Each such cavity contains a molecule of dichloromethane solvent, Fig.…”