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Iron complexes catalyze the activation of 1:1 HOOH HCl that facilitates the chlorohydroxylation of olefins and chlorination of hydrocarbons through (HCl) (L(x)FeIV(OH)Cl), an intermediate formed through a Fenton process. This intermediate, which is more reactive than HOCl, reacts with olefin substrates and saturated hydrocarbons in a highly efficient manner and in selective substrate solutions to yield chlorohydroxo and chloro derivatives.

Solvent effect highly influences the chemoselectivity of the free radical chlorination of cyclopropane. Internal pressure of the solvent is related to the ratio between ring-opened and hydrogen-abstraction products. Gas and condensed-phase chlorination of cyclopropane differ due to the solvent pressure effect of the phase. Results obtained from extrapolation techniques are in good agreement with the experimental data.

The synthesis and isolation of the elusive fullerene cage ([C.sub.2v]-[C.sub.72]) is described. The [C.sub.2v]-[C.sub.72] cage is captured by in situ chlorination to form [C.sub.72][Cl.sub.4] and the chlorination pattern and resulting stability of [C.sub.72][Cl.sub.4] are discussed.

Pd[(OAc).sub.2]-catalyzed aromatic C-H chlorination is analyzed and dinuclear Pd(III) complexes are proposed as intermediated. Kinetic data obtained during catalysis and structural information of relevant intermediates is used for proposing a Pd[(II).sub.2]/Pd[(III).sub.2] catalysis cycle for Pd[(OAc).sub.2]-catalyzed aromatic C-H chlorination.

Computational methods were applied to study the mechanism of the chlorination reaction of SyrB2, a representative [alpha]-ketoglutarate dependent halogenase. CASPT2 calculations for the spin state splittings in the oxoferryl species supported the conclusion that once the [Fe.sup.IV]=O intermediate is formed, the reaction proceeds on the quintet potential energy surface.

A manganese porphyrin mediated reaction of different unactivated alkanes with sodium hypochlorite as the chlorine source was performed to obtain alkyl chlorides as major products with only trace amounts of oxygenation products. The regioselectivity and the preference for C[H.sub.2] groups in the aliphatic C-H bond chlorination could be attributed to nonbonded interactions between the alkyl groups on the substrates and the aryl groups of the manganese porphyrin.

A new [C.sub.1]-symmetric non-IPR hollow isomer, [super #23863][C.sub.78], was captured as [super #23863][C.sub.78][Cl.sub.8] and then subjected to a regioselective substitution reaction with benzyl hydroperoxide to obtain [super #23863][C.sub.78](OOC[H.sub.2][C.sub.6][H.sub.5])[Cl.sub.7]. The differences observed in in C-Cl bond length, intermediate stability, and steric effects of the involved molecules accounted for the chemical regioselectivity of the substitution reaction.

The halogenase gene prnA from pyrrolnitrin biosynthesis was introduced into Streptomyces coeruleorubidus to perform an efficient in situ chlorination of the uridyl peptide antibotic pacidamycin. The installed chlorine provided a selectably functionalizable handle enabling synthetic modification of the natural product using mild cross-coupling conditions in crude aqueous extracts of the culture broth.

The first example of a reagent controlled organocatalytic enantioselective chloroactonization reaction is reported. Various N-chlorinated hydantoins as the terminal chlorenium source is used to cyclize several 4-aryl pentenoic acids in the presence of 0.1 equiv of [(DHQD).sub.2]PHAL.

The article discusses a new approach, which can be used for the total synthesis of the antimitotic bicyclic peptide celogentin C. The various chemical shifts taking place in the process are shown to be highly temperature and concentration dependent.

Several techniques are simultaneously applied to explain the characterization and synthesis of the various catena-phosphorous cations. These cations are shown to contain numerous phosphinophosphonium bonds, which are found to exhibit a strong coordinate nature.

The analysis of the J-based configuration analysis method in chlorinated hydrocarbons and chlorohydrins is described along with the development of a spectroscopic database that has facilitated the configurational assignment of these structures. Certain diastereomeric subclasses of 4,5-dichloro-2,3-epoxyhexane-1-ols have displayed a propensity to undergo ring-opening reactions at C-3 with concomitant inversion of configuration at the neighboring C-Cl at C4, implicating the intermediacy of chloronium ions.

The literature data for the partial rate factors and (ln) for [S.sub.E]Ar processes are compared to theoretical reactivity parameters to rationalize the reactivity and regioselectivity of the electrophilic chlorination, nitration, and alkylation of benzene derivatives. The observed variations of electron density at the different arene ring positions and the experimental partial rate factors for the chlorination and nitration reactions are attributed to strong steric influences on the reaction rates for substitutions involving the bulky benzyl moiety.

Muironolide A, a new chemical entity with an unprecedented chlorinated hexahydro-1H-isoindolone skeleton, is isolated from the same marine sponge, Phorbas sp. that has also provided phorboxazoles A and B. Muironolide A is the first macrolide bearing an esterified trichloromethyl carbinol and is produced by a cyanobacterium that has also made phorbasides.

The addition of chlorine atoms to conjugated cores is shown to be general, effective route for designing n-type air-stable organic semiconductors. The calculations and cyclic voltammetry measurements in solution have shown that the chloro-functionalized molecules have a slightly smaller HOMO-LUMO gap and a lower LUMO level than the fluoro-containing molecules.

The direct spectroscopic study of the catalytic hydrodechlorination of 1,1-dichloroethene in [H.sub.2]O by using surface-enhanced Raman spectroscopy (SERS) is presented. The results have provided the evidence of the room-temperature catalytic hydrochlorination of a chlorinated solvent, an important pathway for groundwater cleanup, as a sequence of dechlorination and hydrogenation steps.

A two-step chlorination/azidation process is developed for the chemical passivation of Si(111) surfaces with azide groups and the chemical and structural characterization of those surfaces are described. The [N.sub.3]-/Si(111) surface is useful for secondary functionalization through the Cu(I)-catalyzed Huisgen 1,3-dipolar cycloaddition and the reduction of the [N.sub.3]-/Si(111) surface using the Staudinger reduction method has produced an amine-terminated surface for the coupling of carboxylic acid molecules.

Study is presented to confirm that purified KtzQ and KtzR are tandem acting halogenases that catalyze the regiospecific dichlorination of L-tryptophan to produce 6,7-dichlorotryptophan.

A two-step chlorination/Grignard process is used to develop a new method to protect silicon surfaces with C[H.sub.3]-CH=CH-MgBr organic molecules. The results provide insight into the functionalization of Si surfaces with C[H.sub.3]-CH=CH-MgBr organic molecules which nearly gives full coverage of Si atop sites, for application in molecular electronics, energy conversion, catalysis, and sensing.

The preparation, photophysical and anion-binding properties of a series of di-, tri-, and tetrapodal anion-binding hosts based on aminopyridium units with pyrenyl reporter groups are described. The chloride addition has resulted in an increase in the intensity of the pyrenyl monomer emission as chloride binding reduces the acceptor ability of the pyridinium groups.

The effects of tailored porosity on the hydrogen sorption capacity are studied and a large number of carbide-derived carbons (CDC) materials are synthesized using different starting materials and chlorination temperatures to explore the effect of variable pore size and volume. The results show that a large volume of small pores with narrow size distributions is vital to high hydrogen uptake.