Inter- /intra

In addition to the multiple processes involving two Diels-Alder reactions in intra-intra, inter-intra or inter-inter molecular sequences, other processes have... 

Gresh N, Cisneros GA, Darden TA, Piquemal J-P (2007) Anisotropic, polarizable molecular mechanics studies of inter-, intra-molecular interactions, and ligand-macromolecule complexes. A bottom-up strategy. J Chem Theory Comput 3 1960... 

Sodium(23Na) Sodium distribution inter/intra cellular sodium Na... 

An inter-intra-intramolecular carbopalladation cascade, initiated by the alkenylpalladium bromide intermediate from /3-bromostyrene 74 inserting into one of the triple bonds of the diyne 73, yields the ring-annelated fulvene derivative 75 (Scheme 22). ... 

Because the rates of this reaction are very rapid, normal sampling techniques were not satisfactory and an infrared technique was used. This esterification reaction was shown to be about 100 times faster than the disproportionation reaction and inter-intra-molecular assistance was also found to be important. This assistance seems to be a common pattern in acid-catalysed processes of oligosiloxanols in inert solvents. In dioxane solvent the redistribution kinetics can be interpreted in terms of an unzipping mechanism. The ratedetermining step is terminal silanol cleavage by water forming dimethylsilanediol which rapidly reacts with other substrate silanols (Scheme 4). 

Many other related but alternative routes to benzene derivatives are conceivable. One inter-intra cascade carbopalladation route which is potentially highly selective is shown in Eq. 1 of Scheme 46 [11]. Another proceeds via cyclic allenylpalladation of alkynes followed by cross-coupling with PhB(OH)2 [127] (Eq. 2 of Scheme 46). Yet another related process is the synthesis of naphthalene derivatives shown in Eq. 3 of Scheme 46 [128]. If the regioselectivity problem could be overcome, it would provide an attractive route to naphthalenes. 

We have described a new system of polymeric snpports based on multifunctional, exceptionally sterically hindered carbosilane moieties, grafted with block poly(vinylmethyl-co-dimethyl)siloxane arms. They offer uniformly periphery-distribnted active sites (-CH = CH moieties) and can be used for preparation of novel catalysts. Platinum was thus attached to the polymers via coordination to vinyl gronps. The materials used in hydrosilylation of vinylsilanes can be considered as an alternative for traditional platinum catalysts. The utility of the catalysts seems to be dependent on the ratio [D]/[V] in the copolysiloxane arm. Those with too high amonnt of vinyl groups suffer from poor solubility and catalytic performance dne to excessive inter/intra-chain coordinative cross-linking. 

Tandem Inter-Intra-Molecular Cyclizations of Zirconacycles 1251... 

Zirconacyclopentadienes 23 (R = R = R = R = Et, Pr", Bu", M = Zr, Cp =Cp) react with l,4-dibromo-2-butyne in the presence of CuCl via a tandem inter-intra-molecular cyclization to yield 2,3,4,5-tetrasubstituted styrenes (Equation 11) <2002T1107>. 3-Chloro-(2-chloromethyl)propene reacts with the same set of zirconacyclopentadienes in the presence of CuCl to yield tetrasubstituted methylene cycloheptadienes. Reaction with 3,4-dichlorobutene under identical conditions yields vinylcyclohexadienes. In both cases, tandem inter-intra-molecular allylation occurs. 

Fluorescent hydrophobes (naphthyl and pyrenyl groups) incorporated into the polysulfobetaines are a powerful tool for studying the formation of intra-and interpolymer aggregates in aqueous and aqueous salt solutions [85,229-231]. Intermacromolecular hydrophobic association is observed as an increase in the excimer emission relative to that of the monomer emission, where h/Iu is the ratio of intensities of excimer and monomer fluorescence which reflects the extent of inter/intra macromolecular interactions. Intramolecular micellization is easily monitored by the quenching efficiency of the thallium ions. The decrease of h/Iu reflects the breaking of the intra- and interchain associations in aqueous salt solutions, leading to chain expansion. 

The behaviour of pectic substances in solutions involves both short and long range interactions among all the constituents of the macromolecule as well as interactions with the solvent molecules and the ions in the solutions. The calculations reported here explain the aggregation of PGA chains in acidic media as due to the formation of a network of inter-intra chain hydrogen bonds. Also the gel formation of Na- and Ca-Pectate is well reproduced. 

Selectivity and productivity depend on sorption and diffusion. Sorption is dictated by thermodynamic properties, namely, the solubility parameter of the solute(s)/membrane material system. On the other hand, the size, shape, molecular weight of the solute, and the availability of inter/intra molecular free space of the polymer largely govern the second property, the diffusion coefficient. For an ideal membrane, both the sorption and diffusion processes should favor the chosen solute. If one step becomes unfavorable for a given solute the overall selectivity will be poor [28]. 

PK characteristics Linear with dose and time, iow inter/intra subject variabiiity Non-linear with dose and time, high inter/ intra subject variability... 

On the other hand, a C-S cyclopentadiene moiety induced almost no face discrimination on addition of dimethyl acetylenedicarboxylate to 9,10-dihydrofulvalene (266) (Scheme 63). Products (268) and (270) result from a tandem inter-/intra-molecular Diels-Alder reaction (domino Diels-Alder reactions). 

These data indicate that the intramolecular interactions which prevailed in dilute solution and which remained "locked in" the solid polymer upon freeze drying are still maintained upon dissolution in xylene. The resulting "solutions" in xylene remain unchanged at ambient conditions over periods of months. It appears that equilibration of inter/intra associations readily occur upon dissolution or dilution in dioxane with S-PS at 1.7% sulfonation levels. However, with the same sample dissolved in a solvent of lower polarity, such as xylene, equilibration upon dilution either does not occur or is very slow. The addition of cosolvents such as alcohols expedites this equilibration. At different sulfonate levels, with different cations or different backbone molecular weights the situation may be different. 

It can be noted that this reaction Is closely analogous to the free radical inter-intra-molecular polymerization discovered by Butler and Angelo (11) In which a difunctional monomer undergoes such efficient ring closure that a soluble linear polymer is obtained instead of a crosslinked or three-dimensional product. 

In the case of the polyketals the condensation of a tetrad with a diketone might at first glance be expected to form a cross-linked polymer, but the ring closure to the six-membered ring is so efficient that a linear soluble product results. Thus the ketal formation can be viewed as a special case of inter-intra-molecular condensation polymerization. 

Four subtypes of this domino reaction are possible, in which each cycloaddition step can be intra- or intermolecular [12-14]. The domino intermolecular [4 -F 2]/ intramolecular [3 + 2] cycloaddition has been studied extensively, mainly by Denmark and coworkers [12]. The domino intermolecular [4 + 2]/intermolecular [3 + 2] cycloaddition, which has been studied less extensively [13], mostly leads to a lower degree of stereoselectivity than the domino inter/intra cycloadditions. From a combinational point of view however, domino inter [4 + 2 /inter [3 + 2] cycloadditions are more attractive as a high degree of structural diversity can be obtained from simple building blocks. 

Bioavailability Acceptable, allowing therapeutic levels, predictable, low inter/intra subject variability Unpredictable, therapeutic levels not reached, high inter/intra subject variability... 

These catalytic reactions require reasonably high pressures and temperatures and, so far, infrared spectroscopy has been the only spectroscopic technique used to monitor them. Although useful information has been obtained in this way, it is generally impossible to obtain unambiguous structural Identification and mechanistic inter-/intra-exchange data which are of lnq>ortance in establishing reactivity patterns of intermediates that are present under these conditions. These are a prerequisite for the basic understanding of the mechanism of these catalytic processes. 

Linear with dose and time, low inter/intra subject variability... 

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