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Regioselective phosphorylation of rctt tetranaphthyl resorcinarenes gave monofunctionalized derivatives with eight phosphamide groups immobilized on the macrocyclic matrix, as well as heterofunctionalized derivatives containing hydroxyl groups on the vertically oriented benzene rings and phosphorus fragments on the planar benzene rings.

New phosphorylated calix [4]resorcinarene and cavitands were synthesized. Their extrac tion ability toward La III , Gd III , and Yb III ions was studied. The cavitands are more efficient extracting agents than octasubstituted calix [4]resorcinarenes. The nature of substituents at the nitrogen atom at the upper rim and hydrophobic substituents at the lower rim exerts a substan tial effect on the solubility of the extracted complex in chloroform. Coordination of two lanthanide ions with an extragent molecule results in their efficient but non selective extrac tion. The literature and our spectral ( 31 P NMR) data suggested that the ligand in the extracted complex has most probably a "kite" conformation.Increasing interest in selective and efficient methods for extraction of ions of 4(5)f elements is caused by their use in nuclear fuel or radioactive waste processing. 1 Due to similarity of the electronic properties of 4f and 5f atoms, lanthanide ions represent a convenient model of radioactive actinides, whose handling is hazardous and requires special care.Separation of lanthanide ions is a complicated prob lem, because their thermodynamic parameters of com plex formation are similar due to the ionic character of bonding. 2 Unlike alkaline and alkaline earth metals, high selectivity of lanthanide extraction is hardly attainable, because the change in the stability constants along the series is determined by the result of opposite effects of different factors: size, solvation, metal ion charge, ligand mobility, etc. 3 High coordination numbers of lanthanides are a prerequisite for their coordination by macrocycles. 4 Efficient extraction is achieved in the case of macrocyclic compounds that actually and selectively bind specific metal ions through the polycentered interaction, when the bind ing sites of the macrocycle and substrate are in geometric correspondence. High lipophilicity of the most part of metal ion complexes with calixarenes in combination with high efficiency serves as a reason for the use of calixarenes in liquid extraction. 4,5 The highest efficiency and selectiv ity of extraction were observed for functionalization of calixarenes by substituents containing the P=O groups. 6 It is known 4,7-15 that immobilization and pre organization of phosphineoxide, carbamoyloxide, and carbamoyl phosphate groups at the rim of the calixarene or cavitand matrix enhance the efficiency and selectivity of extraction. The degree of lanthanide extraction by the carbamoyl phosphineoxide extracting agents decreases in the order La III ≈ Eu III > Yb III . 10 Calix[4]resorcinarenes are conve nient platforms for extracting agents because make it pos sible to change simultaneously both the complexation properties and hydrophobicity. Since the pre organiza tion of donor centers affects the selectivity of complex formation with lanthanide ions, it is natural to expect that the complexation properties would change substantially on going from the calix[4]resorcinarene matrix to related cavitand structures. Examples for using pho...

New derivatives of heterofunctionalized resorcinarenes differing by the nature, number, ratio, and orientation of functional groups were obtained by modification of free reactive centers in the phosphoresorcinarenes of different types.Currently great attention is paid to the design of the receptor systems that can act as chemosensors or extractants. The most common matrices for their creation are macrocyclic molecules containing free cavities and a large number of reaction centers located in a certain mode relative to each other [1][2][3][4]. These compounds include resorcinarenes and their modified analogs. Due to the conformational lability of these molecules and presence of hydroxy groups and the ortho position of benzene rings at the macrocycle whose reactivity can be controlled, the resorcinarenes form a convenient basis for the design of complex compounds with polyfunctionalized cavity systems [5-10].Our goal was to synthesize derivatives of the new heterofunctional resorcinarenes and consider the ways to modify the free reaction sites of phosphoresorcinolarenes of various types.To implement this task we used a common scheme: the resorcinarenes were phosphorylated with phosphorous amides, the phospho(IV)resorcinarenes formed were transformed in the phosphorus(IV) resorcinollarenes, and various functional groups were introduced into the latter molecules.Depending on the required regioselectivity of the process, we selected as the basic compounds the resorcinollarenes I with certain substituents in methylidene bridges and ortho position of benzene rings of the macro-cyclic framework.As a platform for the synthesis of new orthofunctionalized phosphocavitands served ortho-bromotetra(phenylethyl)resorcinarene Ia, due to its boat conformation, that is convenient for the phosphocyclization [9,11], and to the presence of easily replaceable bromine atoms in the ortho positions of benzene rings of the macrocyclic skeleton [12][13][14][15] (Scheme 1).The cyclophosphorylation of Ia with tripiperidylphosphite was performed by the standard method [16,17] in dioxane at room temperature. To the formed phosphorus(III)cavitand was added sulfur without its isolation from the reaction mixture (Scheme 1). Two singlet signals with equal integral intensities appeared in the 31 P NMR spectrum of the isolated tionamidophosphatocavitand II and the doubling of signals of the the benzene rings meta-protons of the framework in the 1 H NMR spectrum indicated the implementation of the kite conformation [17,18].The phosphorus(IV)cavitand II was brpoght into the reaction of electrophilic substitution. Compound II was treated with BuLi, then to it was added either methylchloroformate, which led to ortho-methoxycarbonyl derivative III (Scheme 1, a), or sequentially trimethylborate and hydrogen peroxide with sodium hydroxide solution, which completed by the formation of the ortho-hydroxylated cavitands IV (Scheme 1, b). Further, in the interaction of IV with acetic anhydride ortho-acetylated cavitand V was obtained (Scheme 1, c).Compounds III...

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