Monofunctionalised resorcinarenes

A convenient methodology for introducing single functional groups to the lower rim of resorcinarenes is described. The methodology allows for very convenient differential protection or derivatisation of the upper and lower rims, and a wide range of functional groups (alcohol, carboxylic acid, thiol, amine, carbamate, alkyl halide) can be incorporated as a single unit at the lower rim, opening up the way to further modification at this point and generally widening the scope for further utilising resorcinarenes. Furthermore, our approach has enabled us to link two resorcinarenes together to form novel resorcinarene dimers.     

Regioselective acylation of aminoresorcinarenes

The acid catalyzed hydrolytic cleavage of the oxazine rings in the readily available tetraoxazine derivatives of resorcinarenes results in tetraaminoresorcinarenes. A similar process applied to C₂-symmetrical bisoxazine resorcinarene tetratosylates affords C_2v-symmetrical resorcinarenediamines. The mild acylation of these resorcinareneamines with BOC-anhydride or para-nitrophenyl ester proceeds selectively at the nitrogen atoms without affecting the hydroxyl groups. Most of the resulting resorcinareneamides are thus obtained in preparative yields and can be easily purified by simple crystallizations. In the crystalline state the compounds obtained are found to bind chloride anions through hydrogen bonds and electrostatic interactions and to display a chiral arrangement of hydrogen bonded functional groups at the wide rim of the macrocycle.     

带荧光基团蒽的正庚醛和正丁醛ReSOrcinarenes母体衍生物的合成研究

合成正庚醛、正丁醛Resorcinarenes母体,经生成酯衍生物后同－9蒽甲醇反应,合成了带荧炮光基团蒽的正庚醛、正丁醛Resorcinarenes母体衍生物,考察了各种因素对产物产率的影响,并给出了产物的IR,^1H NMR,MS及UV谱数据。     

Ethyl Pyrogall[6]arene and Pyrogall[4]arene: Synthesis,Structural Analysis and Derivatization

In the acid-catalyzed synthesis of ethyl pyrogallarene, a novel hexamer, ethyl pyrogall arene, is obtained as a readily isolable minor product. Pyrogallarene can be isolated from the reaction mixture in three different ways yielding the hexamer in different forms and stabilities. Crystallization from DMSO and then recrystallization from acetone gives a stable crystalline solid, recrystallization directly from acetone yields an unstable white powder, while direct recrystallization from THF gives a stable white powder. Both pyrogallarene and pyrogallarene crystallize readily with DMSO filling the voids in the crystal lattice. Co-crystallization studies of the hexamer isolated by recrystallization from acetone resulted in a novel directly hydrogen-bonded capsule formed by two pyrogallarenes and an included TMA cation, while the DMSO/acetone isolated product yielded the intact hexamer with clathrate-type TMA inclusion.     

Use of bis-(aminol) ethers derived from N-(S)-(−)-α-methylbenzylamine in reactions with resorcinarenes and double Mannich reactions

The synthesis of some chiral bis-(aminol)ethers are described. Reaction of a solution of the resorcin[4]arene derived from propanal with N,N-bis(methoxymethyl)-N-(S)-(−)-α-methylbenzylamine in toluene at 85 °C initially afforded a 1:1 mixture of two diastereoisomeric tetrakis(benzoxazines). Further, heating of this mixture under reflux in ethanol for 24 h afforded the crystalline (αS),(S)-diastereoisomer in 77% yield. N,N-bis(ethoxymethyl)-N-(S)-(−)-α-methylbenzylamine and N,N-bis(ethoxymethyl)-N-(R)-(+)-α-methylbenzylamine were reacted with β keto esters to afford a 1:1 mixture of the diastereoisomeric double Mannich adducts. Two of the double Mannich adducts were converted into tricyclic ABE analogues of the alkaloid methyllycaconitine 1.     

Introduction of Water-Solubilizing Groups at the Lower Rim of Tolylpyridine-Bridged Cavitands

In this paper the preparation of water-soluble methylene-bridged cavitands presenting either positively or negatively charged groups at the lower rim following three different synthetic routes is reported. Moreover, four anionic sulphate functions have been successfully inserted on a tolylpyridine-bridged cavitand in order to carry out the self-assembly of coordination cages in water.     

Resorcinarenes的合成及其边缘化学修饰（Ⅰ）

探讨了烷基醛类（乙醛,丙醛）的Ｒｅｓｏｒｃｉｎａｒｅｎｅｓ的合成及其边缘化学修饰（乙酰化,甲基化）,研究了各种因素对Ｒｅｓｏｒｃｉｎａｒｅｎｅｓ的影响。确定了较佳反应条件。     

Binding properties and self-assembly of C2v-symmetrical resorcin[4]arene tetrabenzoates

In the crystalline state two molecules of resorcin[4]arene tetrabenzoates and four chloride anions form molecular wraps containing two Et₃NH⁺ cations. The structure and composition of the wraps depend on the length of the alkyl chains at the narrow rim of the macrocycle. Resorcin[4]arene tetrabenzoates interact with ammonium salts in CDCl₃.     

Synthesis of novel, boron-containing cavitands derived from calix[4]resorcinarenes and their molecular recognition of biologically important polyols in Langmuir films

An efficient synthetic route for the synthesis of cavitands derived from calix[4]resorcinarene and its tetrabromo derivative was elaborated. A large-scale preparation was achieved in excellent yield, by replacing the high-boiling solvents with acetone. The tetrabromocavitands were transformed into tetra-boronic acid cavitands via lithiation with butyllithium and reaction with triethylborate. Two lipophilic cavitands bearing four boronic acid residues were demonstrated to form stable Langmuir monolayers at the water-air interface. These cavitand receptors differ in bridging unit between oxygen atoms, i.e. one contains a one-carbon unit and the other a two-carbon unit. l-sorbose, d-galactose, d-glucose, and d-cellobiose were selected for molecular recognition studies using the Langmuir techniques. The unsubstituted tetra-n-undecyl calix[4]resorcinarene was used as a reference receptor compound. Differences in surface potential were diagnostic of the different types of binding forces, which can occur.     

Extraction and Dispersion of Large Gold Nanoparticles in Nonpolar Solvents

Gold nanoparticles up to 70 nm in diameter could be extracted from aqueous solutions into nonpolar organic solvents by tetrathiolated resorcinarenes 1 and 2. The resorcinarene-coated nanoparticles formed stable dispersions in toluene and chloroform and could be passed through a crosslinked polystyrene column without significant degradation, but exhibited variable resistance to alkanethiol-induced flocculation. Gold nanoparticles encapsulated by resorcinarene 2 were found to be exceptionally stable even in the presence of propanethiol and dodecanethiol, with an approximate dispersion half-life of one month at room temperature.