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Research demonstrates the synthesis of alcohol complexes of osmium nitrosyl porphyrins for the first time. Data reveal that these heme-containing biomolecules undergo facile deprotonation mediated by pyridine to yield cognate alkoxide derivatives.

Research demonstrates that low molecular weight organic compounds can be prepared from functionalized carbosilane dendrimers used as soluble supports. The methodology employs enolate-imine condensation and dendritic species that have only one functional group per peripheral Si-site.

This paper examines the various steps involved in the organic synthesis involving monocarbanionic organometallic reagents. Research reveals that these compounds in the presence of titanium derivatives behave as dicarbanionics when reacting with electrophiles.

Research describes the synthesis of porphyrazinediols, their conversion into solitaire complexes, and chemical oxidation of the polydentate noninnocent macrocycles. Results demonstrate that porphyrazinediols are a novel class of redox-active ligands whose diol chelating group is directly attached at the beta-positions of the macrocycle.

The regiochemistry of the addition of alkyl cuprates to chiral silabromoallenes is dependent on the presence of the silicon nucleus of silylated bromoallenes. Polysubstituted chiral silaalkylallenes were formed by the stereospecific substitution of the silylated bromoallenes which also involves a formal bromine SN2 nucleophilic substitution of the sp2 carbon. A propragylic Cu(III) intermediate was also formed during the initial reactions due to the displacement of the bromine by nucleophilic copper.

Trisubstituted fluoroalkenes were synthesized by the reaction of organolithium reagents to trifluoromethyl enol ethers and thio enol ethers. The course of the reaction of nonterminal CF3-substituted vinylic compounds with organolithium reagents reagents is strongly dependent on the substitution pattern. The formation of E-trisubstituted fluoroolefins also involved the instantaneous stereoselective elimination of lithium ethoxide/thioethoxide.

A novel method for the enantiomeric enrichment of allenedicarboxylates was developed based on the complexation of the starting compound with (+)-Eu(hfc)3. The synthetic process was characterized by the introconversion of diastereoisomeric complexes and subsequent enrichment of the preferred compound with the europium reagent. The synthetic process also involved the reconstruction or reordering of the higher-order complex in the reaction solution.

A novel method for the synthesis of a series of 4,6-dideoxypyranoside derivatives was developed based on the utilization of (TMM)Fe(CO)3 complexes [(TMM) = trimethylenemethane]. The synthetic strategy was characterized by the reaction of a racemic compound with 1-methoxy-3-[(trimethoxylsilyl)oxy] -1,3-butadiene in BF3.Et2O. The resulting intermediate product was reacted with trifluoroacetic acid to form single diastereoisomers of the dihydropyrone complex.

A series of 3,4-syn-adducts was synthesized by the reaction of omicron-protected polyhydroxy ketones with sigma-type Grignard reagents. The synthetic process was characterized by the diastereoselective Grignard carbonyl additions which led to the formation of a reactive conformation and a ground-state conformation. The intermediate ground state conformation was also dependent on the presence of acetonide protective groups.

A novel method for the synthesis of 3-arylalkyl-delta3- and 3-alkenyl-cephems was developed based on the utilization of an organocopper species that was ligated by terpyridine or bipyridine. The synthetic process was characterized by the utilization of an organocopper species which was generated by the transmetalation of organotins with copper(I) chloride. The reaction process also involved the formation of a coordinately saturated vinyl-copper(I) from a terpyridine intermediate. Furthermore, the target compounds were produced as cross-coupling products.

Optically active dicarbonyl cyclopentadienyliron(vinyl ether) BF4 salts were synthesized and utilized as chiral 3-hydroxypropionate 2,3-dication equivalents for the formation of beta, delta-dihydroxy esters. The synthetic strategy was characterized by the formation of of the diastereoisomers from the reaction of the starting material with (S)-propane-1,2-diols. The organometallic salts behaved as stabilized enantioselective carbocations toward carbon nucleophiles and mediated the formation of the desired esters via redox-promoted methoxycarbonylation.

Thiophene-functionalized tetrathiafulvalene (TTF) derivatives were synthesized from the reaction of 4,5-bis(2-thienyl)-1,3-dithiol-2-one with a variety of bis-substituted 1,3-dithiole-2-thiones in triethyl phosphide. Analysis of the molecular structure of the thiophene-substituted TTF electrons donors indicated the presence of orientational disorder in the two thiophene substituents. Furthermore, 4,5-bis(2-thienyl)-4',5'-bis (ethylenedithiolo)tetrathiafulvalene exhibited an ethylenedithiolo fragment with a twisted chair conformation.

Alpha,alpha,alpha',alpha'-tetraaryl-1,3-dioxolane-4,5-dimethanol (TADDOL) derivatives were utilized for the synthesis of a series of functionalized polymers-grafted Ti-TADDOL complexes. The synthetic strategy was characterized by the formation of supported TADDOL derivatives that were grafted on polymeric resins. Furthermore, the resulting TADDOL complexes efficiently catalyzed the reaction of cyclopentadiene with 3-crotonyl-1,3-oxazolidin-2-one.

A novel method for the preparation of enantiomerically pure monosubstituted aziridines was developed based on the reaction of an aziridine tosylate with a primary organocuprate reagent. The synthetic strategy was characterized by the formation of ring-opened intermediates due to the attack of cuprate to the least-substituted carbon of the aziridine ring. Subsequent ring closure of the intermediates via displacement of the tosyl ester in the presence of chiral solvating agents led to the formation of the aziridines.

The one-pot conversion of aromatic aldehydes to allenes in the presence of titanium-substituted ylides involved three reaction processes. The formation of allenes was characterized by the elimination of titanium oxides to form vinylphosphonium salts which produced allenic phosphorane via aldehyde-induced deprotonation and condensation. The ylide species involved in the one-pot synthetic process were metal complexes with different titanium ligand substitutions.

The reaction of titanium-substituted ylide species with carbony compounds led to the formation of vinylphosphonium salts. The stepwise coupling procedure involved a double olefination and a single reaction using boron-substituted phosphorus ylide. The resulting vinylphosphonium salts undergo deprotonation and condensation reactions with an aldehyde to produce 1,3-disubstituted allenes. Furthermore, irradiation of the vinylphosphonium salts induced reversible isomerization forming Z-vinylphosphonium isomers.

Substituted isoquinolones were synthesized by the sequential carbophilic addition of organolithium reagents and cyclization of N-phenethylimides by N-acyliminium ion. The synthetic process was characterized by the introduction of functionality on the pendant side chain of substituted isoquinolones to produce useful precursors for the construction of isoquinoline alkaloids. The key step to the reaction also involved the N-acyliminium ion-mediated carbon-carbon bond formation reactions.

The regiochemistry of the addition of alkyl cuprates to chiral silabromoallenes is dependent on the presence of the silicon nucleus of silylated bromoallenes. Polysubstituted chiral silaalkylallenes were formed by the stereospecific substitution of the silylated bromoallenes which also involves a formal bromine SN2 nucleophilic substitution of the sp2 carbon. A propragylic Cu(III) intermediate was also formed during the initial reactions due to the displacement of the bromine by nucleophilic copper.

Trisubstituted fluoroalkenes were synthesized by the reaction of organolithium reagents to trifluoromethyl enol ethers and thio enol ethers. The course of the reaction of nonterminal CF3-substituted vinylic compounds with organolithium reagents reagents is strongly dependent on the substitution pattern. The formation of E-trisubstituted fluoroolefins also involved the instantaneous stereoselective elimination of lithium ethoxide/thioethoxide.

A general method for preparing functionalized dialkylzincs proceeded with the hydroboration of olefins with Et2BH, which yielded diethyl(alkyl)boranes, followed by a boron-zinc exchange mediated by diethylzinc, which provided a variety of polyfunctional primary, secondary and benzylic diorganozincs. Reaction of these diorganozincs with various electrophiles in the presence of CuCN*2LiCl gave excellent yields. Their addition to aldehydes proceeded with high enantioselectivity, affording a unique access to polyfunctional secondary alcohols with often excellent optical purity.

A new method was developed for the synthesis of higher yields of isoindolones by adding omicron-lithiated benzoates and N-methylbenzamide to imines that are activated with BF3. The reaction of omicron-lithiobenzoates to imines with alpha hydrogens exhibited high diastereoselectivity without the presence of competing proton transfer. The reaction of isopropyl omicron-iodobenzoate with BF3.OEt2 produced 48% yield of isoindolone. The reaction was enhanced due to the faster rate of lithium-iodide exchange compared to the lithium-bromide exchange.

The reaction of thiol-amide-thiourea (TATU) ligand with Re(superV)O complexes yields (1-phenyl-3-(2-((2-thioacetyl)amino)ethyl)thioureato)oxorhenium(V) neutral complex, which is a new N2S2 chelate. The complex has a pseudo square pyramidal geometry with deprotonated thiol S, amide N, thiourea N, and thiocarbonyl S in the basal plane, and oxo group at the apical position. The thiourea unit of TATU ligands forms a four-membered chelate ring, which enables it to synthesize multidentate ligands. X-ray crystallography and NMR spectra are used to characterize the complex.

Syntheses of four-, five- and six-membered alkenylidenecycloalkanes involve the cyclization of acetylenic alkyllithium having a methoxy group at the distal propargylic position. Length of the tether influences the formation of allene from intramolecular SN2' ring-closure of omega-lithio methyl propargylic ethers. Silica gel chromatography helps separate cyclized products from uncyclized reactants.

Synthesis of a uracil nucleoside (A) involves an electrophilic addition reaction between 1-(3,5-bis-O-(tert-butyldimethylsilyl)-2-deoxy-D-erythro-pent-1-enofuranosyl) uracil and NBS/pivalic acid. Nucleophilic substitutions of A using organosilicon and organoaluminium reagents produce different types of nucleosides branched at the anomeric position. This stereocontrolled synthesis is assisted by the leaving groups at the 1 position and 2'-beta-Br in A.

Synthesis of the diphenylene-bridged dimers of 1,3,2,4,6-thiaphosphatriazine and 1,3,2,4,6-selenaphosphatriazine and their subsequent reduction to the corresponding diradicals allow the study of their structure and spin distribution vis-a-vis their monomers. The electron spin resonance study shows that, although the two phosphatriazines have similar radical spin distributions, the thia radical dimerizes via an S-S bond while the seleno radical does so via an Se-N rather than an Se-Se bond.

Synthesis of tri- and tetrasubstituted beta-lactones involves the spontaneous intramolecular cyclization of phenyl esters of O-lithiated beta-hydroxyalkanoates. Aldolization of lithium enolates of phenyl esters with aldehydes or ketones produces the corresponding O-lithiated phenyl beta-hydroxyalkanoates. The phenoxy group facilitates the intramolecular cyclization by activating the carbonyl groups.

A method for the synthesis of 4-phenyl-4-decen-2-one was developed based on the cross coupling reactions with organozinc chlorides. The synthetic process involves the formation of 4-phenyl-4-decen-2-one via one-pot-reaction of hydrogen iodide with (Z)-4-iodo-4-decen-2-one. The reaction also involves palladium-catalyzed cross coupling reactions with organozinc chlorides in Pd(PPh3)4. Furthermore, the coordination of the zinc cation with the carbonyl oxygen accelerated the synthetic process.

The kinetics of the metal-mediated [2+2+2]cyclotrimerization of alkyne were analyzed during the synthesis of the metacycle complex of 1,1,1-tris(diphenylphosphinomethyl)ethane (tiphos) ligand. The fulvene complex was formed by the reaction of phenylacetylene to a methylene chloride solution at room temperature. The formation of the fulvene complex involved the initial coordination of alkyne to the metal, the rearrangement of a vinylidene ligand and reductive cyclization to the carbocycle product.

The synthesis and characterization of two novel organometallic nanodimensional macrocycles are described. These complexes exhibit two trans-platinum linear linkages along the sides of the square and platinum or iodonium centers with approximately 90 degrees geometries at the corners of the macrocycle. A simple yet efficient route is offered by the reaction of 4,4'-diiodobiphenyl with 2.2 equiv of Pt-(PPh3)4, via oxidative-addition, to the bisplatinum complex. They are predicted to be useful in organic synthesis and organometallic catalysis.

Reaction of organotin thiolates or organotin selenolates with esters, in the presence of Lewis acids, facilitates the noncoupling synthesis of dihydrotetrathiafulvalene (DHTTF) derivatives and diselenadithiafulvalene derivatives. A comparative study using various Lewis acids indicates trimethylaluminium as the most efficient Lewis acid. Reaction of DHTTF derivatives with TCHQ in different organic solvents forms different charge-transfer salts, revealing the DHTTF derivatives as efficient electron donors.