bluuebunny/crossref_metadata_2025_split huggingface dataset:
The influence of Yb3+ concentration on Yb:YAl3(BO3)4
Authors: Li J. , Wang J. Y. , Cheng X. F. , Hu X. B. , Wang X. Q. 
Published: September 2003

AbstractThe Yb:YAl3(BO3) 4 crystals with different Yb3+ doping concentration have been grown by the flux method. The lattice parameters and decomposition of the Yb:YAl3(BO3)4 crystal with different Yb3+ doping concentration were measured by X‐ray and DTA method. The transmission and fluorescence spectra of Yb3+:YAl3(BO3)4 crystal have been measured. The growth defects of YbxY1‐xAl3(BO3)4 crystals were also detected by using the chemical etching method. The results show that the ytterbium concentration influences these properties of Yb:YAl3(BO3)4. As the Yb3+ concentration increased, the crystal lattice parameter was decreased. At high doping level, the absorption peak concerned at about 980 nm shift to short wavelength. It is also found that the perfection of Yb:YAl3(BO3) 4 crystal with low Yb3+ doping concentration is better than that with high Yb3+ concentration. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis, characterization and structural phase transition studies in trismethylammonium pentachloro barium dihydrate single crystals
Authors: Amirthaganesan G. , Kandhaswamy M. A. , Srinivasan V. 
Published: September 2003

AbstractSingle crystals of trismethylammonium pentachlorobarium dihydrate were grown by slow evaporation method at ambient temperature. The crystals were characterized through powder XRD, thermal, infrared and NMR spectral studies. While the powder XRD pattern confirms the crystallinity of the title compound, the TG indicates the removal of occluded and adsorbed water molecules from the crystal when it is heated up to 86 °C. The TG study also confirms the presence of two water molecules of crystallization which are dehydrated on heating the crystal between 107 °C and 150 °C. The anhydrous compound is found to be stable at least up to 900 °C. The DTA curve shows two endothermic dips corresponding to weight losses observed in the TG curve. The low temperature DSC study shows thermal anomalies during the heating and cooling cycles indicating both first and second order phase transitions. The high temperature DSC shows the stepwise dehydration indicating phase transitions at temperatures 103 °C and 145 °C. The characteristic vibrational frequencies due to methylammonium ion, BaCl5 and other groups are assigned based on FTIR spectra. The NMR spectrum confirms the presence of protons of the methyl group and water of crystallization in the compound. In this paper, an attempt is also made to understand the effect of methyl group on the phase transitions of the compound in comparison with a closely related compound, trisammoniumpentachloro barium dihydrate. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The crystal and molecular structure of bis(tetramethylammonium) hexamolybdate(VI)
Authors: Ghammami S. 
Published: September 2003

AbstractThe crystal structure of the title compound, C8H24N2Mo6O19 was determined by single crystal X‐ray diffraction technique. The crystals are trigonals, space group P‐3c1, with a = b = 10.0176(11) Å, c = 14.089(2) Å, γ = 120°, V = 1224.4(3) Å3, Z = 2. The structure was solved by direct methods and refined by least‐squares methods to a Final R = 0.0316 for 1114 observed reflections with I > 2σ(I). In hexamolybdate anion, six MoO6 distorted octahedra are fused together so that they all share a common vertex. O atoms are of three types: central, terminal and bridging, bonded to six, one and two Mo atoms, respectively. The crystallographic data of the structure was deposited with the Cambridge Data Center as No. CCDC 199679. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Hypersilyl‐Substituted Complexes of Group 1 and 2 Metals: Syntheses, Structures and Use in Styrene Polymerisation
Authors: Feil Florian , Harder Sjoerd 
Published: September 2003

AbstractAlkali and alkaline‐earth metal complexes with sterically demanding hypersilyl‐substituted cyclopentadienyl or fluorenyl ligands [hSi‐Cp or hSi‐Flu; hSi = (Me3Si)3Si] were prepared. The crystal structures of [Li(hSi‐Flu)(THF)2], [K(hSi‐Flu)(THF)], [Ca(hSi‐Flu)2(THF)2], [Sr(hSi‐Flu)2(THF)2] and [Ca(hSi‐Cp)2(THF)] were determined. All structures show the enormous steric bulk of the hypersilyl substituent, which either results in a reduction in the number of solvent molecules in the coordination sphere of the metal or in a distortion of the ligand‐metal interaction. Heteroleptic calcium and strontium complexes with a benzyl ligand (2‐Me2N‐α‐Me3Si‐benzyl) and a sterically demanding hSi‐Flu ligand were prepared and used as initiators in the polymerization of styrene. The polymers produced with the heteroleptic benzylcalcium initiator are enriched in syndiotactic sequences, although they show the same tacticities as polymers obtained with benzylcalcium initiators containing the less bulky Me3Si‐Flu ligand. Introduction of the bulky hypersilyl group in heteroleptic benzylstrontium initiators resulted in a slight increase of the syndiotacticity of the polymers. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Heteroaromatic‐Substituted Mono‐ and Bis(triimidosulfonates)
Authors: Selinka Carola , Stalke Dietmar 
Published: September 2003

AbstractIn this paper we present the syntheses and structures of the metal complexes [(THF)2Li{(NtBu)3S(C4H3NMe)}] (1), [(tmeda)Li{(NtBu)3S(C4H3S)}] (2), [(tmeda)Li{(NtBu)3S(C4H3Se)}] (3), [(THF)4Li2{(tBuN)3S(SC4H2)S(NtBu)3}] (4a) and [(tmeda)2Li2{(tBuN)3S(SC4H2)S(NtBu)3}] (4b). The lithium salts form non‐aggregated soluble molecules rather than infinite insoluble solid‐state lattices like their oxo analogues. The metals are N,N‐chelated rather than tripodally coordinated. Although the S−N bond to the one pendant spectator tBuN group is considerably shorter than in the metal‐coordinated tBuN groups, conjugation of the S−N bonds to the heteroaromatic rings could not be deduced unambiguously from the experimental structures. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Synthesis and Structure of [{(THF)2Li}3Me2Al{(PhNH)2(PhN)4P3N3}], the First Mixed‐Metal Phosphazenate Complex
Authors: Rivals Frederic , Steiner Alexander 
Published: September 2003

AbstractReaction of the trilithium phosphazenate [{(THF)2Li}3{(PhNH)3(PhN)3P3N3}] with one equivalent of trimethylaluminium yields the first mixed‐metal phosphazenate complex [{(THF)2Li}3Me2Al{(PhNH)2(PhN)4P3N3}]. X‐ray structure analysis showed that the Me2Al group is accommodated in an N(exo)−P−N(exo) chelation site of the phosphazenate ligand. Two lithium ions reside in N(ring)−P−N(exo) sites, while the third lithium ion interacts with the ligand solely via an N(ring) atom. NMR spectroscopic data obtained from THF solution indicate a fluxional behaviour of the lithium ions, which oscillate between mono‐ and bidentate coordination sites. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Polar Molecular Precursors for Alkali and Alkaline Earth Metal Clusters and Low‐Dimensional Polymer Structures: the Solid‐State Structures of [CaI(dme)3]I, and cis‐[SrI2(diglyme)2] (dme = CH3OC2H4OCH3; diglyme = CH3(OC2H4)2OCH3)
Authors: Fromm Katharina M. , Maudez William 
Published: September 2003

AbstractTwo new alkaline earth metal halide adducts with oxygen‐donor polyether ligands are described. One of them, cis[SrI2(diglyme)2], features two terminally bonded anions in vicinal positions, and at an angle of ca. 90°. The low bond valence sum of ca. 1.9 indicates how well the cation is shielded by its ligands in the solid state, and that ligand exchange can be expected in solution and upon reaction. The second compound, [CaI(dme)3]I, consists of an ion pair formed by the cationic complex [CaI(dme)3]+ with one anion in terminal position, and one iodide. Both compounds possess a strong dipole moment at the molecular level, but crystallize in centrosymmetric space groups. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
The First Structurally Characterized Diorganoaluminate
Authors: Eaborn Colin , Gorrell Ian B. , Hitchcock Peter B. , Smith J. David 
Published: September 2003

AbstractThe first structurally characterized dialkylaluminate [{Li(THF)}(AltBu{C(SiMe3)3}H2)]2 (3) is dimeric in the solid state with [Li(THF)]+ and [AltBu{C(SiMe3)3}H2]− fragments linked by Li···H−Al bridges. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
A Homologous Series of Base‐Free Organo(alkaline‐earth) Metallocenes: Synthesis and Molecular Structures of [1,2,4‐(SiMe3)3C5H2]2(Ca, Sr, Ba)
Authors: Harvey Melanie J. , Quisenberry Keith T. , Hanusa Timothy P. , Young Jr. Victor G. 
Published: September 2003

AbstractBis[1,2,4‐tris(trimethylsilyl)cyclopentadienyl] complexes [1,2,4‐(SiMe3)3C5H2]2Ae [(Cp3Si)2Ae; Ae = Ca (1), Sr (2), Ba (3)] are isolated from the 2:1 reaction of K[Cp3Si] and AeI2 in diethyl ether. Under the same reaction conditions used for the heavier metallocenes, the corresponding (Cp3Si)2Be compound was not formed, although calculations suggest that the beryllocene would be sterically feasible. Compound 1 crystallizes as a bent monomer from hexanes (ring centroid−Ca−ring centroid = 166.7°) with two η5‐Cp3Si ligands on the calcium atom [Ca−C(av) = 2.63(2) Å]. Metallocene 2, the first crystallographically characterized example of an unsolvated strontocene, is also isolated as a bent monomer (159.4°) from hexanes with two η5‐Cp3Si ligands on the strontium atom [Sr−C(av) = 2.819(2) Å]. Compound 3 crystallizes on sublimation as a coordination dimer in which each barium atom is flanked by two η5‐Cp3Si rings [Ba−C(av) = 3.01(2) Å] and one methyl group from a neighboring Cp′ ring; the intermolecular Ba···C(methyl)′ distance is 3.275(6) Å. The amount of bending observed in 1−3 and other Group‐2 metallocenes varies with the metals, the steric bulk of the cyclopentadienyl ligands, and crystal packing effects, and is not easily predictable. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Synthesis, Structures and Characterization of the Calcium Pyrrolates [Ca{(2‐(dimethylaminomethyl)pyrrolyl}2 donorn] (donor = THF and pyridine, n = 2; DME and TMEDA, n = 1) as Potential Precursors for Solid‐State Applications
Authors: Vargas Wilda , Ruhlandt‐Senge Karin 
Published: September 2003

AbstractThe synthesis and characterization of novel alkaline earth metal pyrrolyl derivatives is described. The target molecules were synthesized using transamination and metallation protocols, involving either the treatment of calcium bis[bis(trimethylsilyl)]amide with two equivalents of 2‐(dimethylaminomethyl)pyrrole (2‐DMAMP) or the reaction of elemental calcium with two equivalents of 2‐DMAMP. Different donors, namely THF, pyridine (py), DME (dimethoxyethane), and TMEDA (N,N,N′,N′‐tetramethylethylenediamine) were utilized to study their influence on the structural chemistry of the target compounds. In order to compare the influence of the metal coordination on the pyrrole ligand, we included the crystal structure of the free 2‐DMAMP ligand. All new compounds were characterized using 1H, 13C NMR and IR spectroscopy in addition to X‐ray crystallography. Crystal data with Mo‐Kα radiation (λ = 0.71073 Å) are as follows: 1: [Ca(2‐DMAMP)2(THF)2], a = 15.440(2) Å, b = 14.992(2) Å, c = 10.175(1) Å, β = 94.9(3)°,V= 2346.6(6) Å3, Z = 4, monoclinic, space group P21/c, R1(all data) = 0.0981; 2: [Ca(2‐DMAMP)2(py)2], a = 9.168(6) Å, b = 10.418(7) Å, c = 13.329(8) Å, α = 85.9(1)°, β = 72.9(1)°, γ = 86.2(1)°, V = 1212.2(1) Å3, Z = 2, triclinic, space group P$\bar 1$
, R1 (all data) = 0.0711; 3: [Ca(2‐DMAMP)2(DME)], a = 10.814(1) Å, b = 12.907(1) Å, c = 15.170(1) Å, V = 2117.3(3) Å3, Z = 4, orthorhombic, space group P212121, R1 (all data) = 0.0729; 4: [Ca(2‐DMAMP)2(TMEDA)], a = 9.403(6) Å, b = 15.810(1) Å, c = 15.417(1) Å, V = 2292.0(3) Å3, Z = 4, orthorhombic, space group Pbcn, R1 (all data) = 0.0997; 5: 2‐DMAMP, a = 10.8820(7) Å, b = 15.2186(10) Å, c = 9.7578(6) Å, β = 109.736(2)°,V = 1521.05(17) Å3, Z = 2, monoclinic, space group Cc, R1 (all data) = 0.0382. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
The Directed Lithiation of Benzenoid Aromatic Systems
Authors: Wheatley Andrew E. H. 
Published: September 2003

AbstractDirected metallation using organolithium bases is one of the best ways of regiospecifically elaborating aromatic systems and their substituents. For benzenoid arenes, deprotonation occurs at the ortho, lateral or peri positions. The reasons for each type of reaction will be considered in the context of the propensities of different directing groups for complex formation with the incoming organolithium base, acidification of the reactive site(s) and post‐reaction stabilisation of the metal ion(s). Discussion will concentrate on structural investigations, for the most part by single‐crystal X‐ray diffraction and/or by multinuclear NMR spectroscopy. Theoretical studies will also be incorporated. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Cooperative THF Ring‐Opening by B(C6F5)3 and a Tellurium Diimide Dimer
Authors: Chivers Tristram , Schatte Gabriele 
Published: September 2003

AbstractThe tellurium diimide dimer [tBuNTe(μ‐NtBu)2TeNtBu] (1) and B(C6F5)3 form a 1:1 adduct which instigates THF ring‐opening to give [tBuNTe(μ‐NtBu)2TeN(tBu)(CH2)4OB(C6F5)3] (3) quantitatively; complex 3 is also formed rapidly when 1 is added to a THF solution of B(C6F5)3. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Structures and Reactions of 1,3‐Diamidodilithium Complexes: the Hemisolvated l‐[CMe2{CHMeN(R)}2Li2·OEt2], the Unsolvated 1:1 Mixed Organo‐amidolithium u‐[CMe2{CHMeN(R′)}2·Li2·(nBuLi)2], and the Product of Oxidative Ring Closure, the Pyrazolidine l‐[(RNCHMe)2CMe2] (R = 2‐iPr‐C6H4; R′ = 2,6‐iPr2‐C6H3)
Authors: Carey David T. , Mair Francis S. , Pritchard Robin G. , Warren John E. , Woods Rebecca J. 
Published: September 2003

AbstractThe hemi‐solvated C2‐symmetric 1,3‐diamidolithium l‐[CMe2{CHMeN(R)}2Li2·OEt2] has been crystallographically characterized. It reacts with oxygen to form the N‐N ring‐closed pyrazolidine l‐[(RNCHMe)2CMe2]. The slightly bulkier Cs‐symmetric amidolithium u‐[CMe2{CHMeN(R′)}2·Li2] forms an unsolvated 1:2 heterocubane complex with nBuLi in the solid state and in solution, as determined by X‐ray crystallography and multinuclear NMR spectroscopy (R = 2‐iPr‐C6H4; R′ = 2,6‐iPr2‐C6H3). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Nucleophilic Substitution of Chloro‐Substituted Enaminones that are Derivatives of Imidazolidine Nitroxides − The Catalytic Effect of the Cyanide Ion
Authors: Roshchupkina Galina I. , Rybalova Tatyana V. , Gatilov Yury V. , Reznikov Vladimir A. 
Published: September 2003

AbstractThe cyanide ion is a catalyst for reactions of nucleophiles with chloro‐substituted enaminones derived from imidazolidine nitroxides, which result in the formation of formal nucleophilic substitution products. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Linear Analogues of Acid‐ and Ester‐Terminated Polyamido Dendrimers: Design, Syntheses, and Physical Properties
Authors: Newkome George R. , Moorefield Charles N. , Epperson Jon D. 
Published: September 2003

AbstractThe synthesis of linear, unnatural amines and carboxylic acids, based on amide connectivity and possessing identical repeat unit architecture to that of analogous dendrimers, was undertaken to assess and compare their physical characteristics. For the series, unexpected insoluble behavior was observed at low molecular weights in contrast to their branched counterparts or other known linear dendritic analogs. Molecular modeling suggests a high degree of intra‐ and intermolecular H‐bonding for the series. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Synthesis of Novel Nucleo‐β‐Amino Acids and Nucleobase‐Functionalized β‐Peptides
Authors: Brückner Arndt M. , Garcia Margarita , Marsh Andrew , Gellman Samuel H. , Diederichsen Ulf 
Published: September 2003

AbstractFour novel β‐amino acids bearing the canonical nucleobases guanine, cytosine, adenine, and thymine in the side chain, are synthesized starting from Boc‐L‐aspartic acid 4‐benzyl ester. The syntheses are accomplished in six steps by the nucleophilic substitution of (S)‐β‐(tert‐butoxycarbonylamino)‐δ‐bromopentanoic acid benzyl ester with the corresponding nucleobase derivative as the key step. The guaninyl and cytosinyl β‐amino acids were built into β‐peptides that were studied by temperature‐dependent CD and UV spectroscopy. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Synthesis and Two‐Photon‐Excited Fluorescence of Benzothiazole‐Based Compounds with Various π‐Electron Donors
Authors: Cao Du‐Xia , Fang Qi , Wang Dong , Liu Zhi‐Qiang , Xue Gang , Xu Gui‐Bao , Yu Wen‐Tao 
Published: September 2003

AbstractWe have synthesized a series of new D−π−A compounds that feature various electron donors and a fixed benzothiazolyl unit as an electron acceptor. The crystal structure of compound 3 [trans,trans‐2‐{4‐[(4‐N‐carbazolyl)styryl]styryl}‐1,3benzothiazole, CSSB] was determined. All these compounds show high fluorescence quantum yields and 3 in toluene gives the most intense blue emission around 450 nm with a quantum yield of Φ = 0.69. When excited at 800 nm by a Ti:sapphire femtosecond laser, these compounds exhibit strong two‐photon‐excited fluorescence (TPEF) in the blue‐to‐orange region. The measured TPEF cross‐section of compound 2 [trans,trans‐2‐{4‐[4‐(N,N‐diphenylamino)styryl]styryl}‐1,3‐benzothiazole, DPSSB], for example, is about 6.1 times that of Coumarin 307. Photophysical data indicate that these compounds are polar in the ground state and have an enhanced polarity in the excited state, and that the electron donating ability of a dialkylamino group is much stronger than that of a diarylamino group. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Highly Shape‐Selective, Biomimetic, and Efficient Deprotection of Carbonyl Compounds Masked as Ethylene Acetals or Dioxolanes Produced from 1,2‐Ethanediol
Authors: Ji Hong‐Bing 
Published: September 2003

AbstractA simple, mild, efficient, and organic solvent‐free biochemical approach for the deprotection of carbonyl compounds protected as 1,3‐dioxolanes through the use of cyclodextrins as catalysts has been developed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Arborol‐Functionalised Tetrathiafulvalene Derivatives: Synthesis and Thin‐Film Formation
Authors: Gall Thierry Le , Pearson Christopher , Bryce Martin R. , Petty Michael C. , Dahlgaard Henriette , Becher Jan 
Published: September 2003

AbstractThe syntheses of a series of novel tetrathiafulvalene derivatives substituted with four side‐chains terminating in hydrophilic amidoalcohol (arborol) groups are reported, for example the tetrathiafulvalene derivative 15. Some of these arborol derivatives formed thin films by spin‐coating from methanol solution onto solid supports such as glass, ITO‐coated glass and gold. The quality of the films improved markedly with an increasing number of alcohol substituents at the periphery of the molecule. Optical absorption spectroscopy showed that oxidative doping of these films could be achieved chemically and electrochemically. The observation of low‐energy bands in the UV/Vis absorption spectra (λmax = 820 nm tailing to ca. 1300 nm) and the moderate levels of conductivity (σrt ≈︁ 10−4 S cm−1) in these doped films strongly suggest that a significant degree of supramolecular order is present, with π‐π stacking of the TTF cores. To the best of our knowledge this is the first time that semiconducting behaviour has been achieved in molecular arborol systems that possess an electroactive core unit. This work offers the prospect of using spin‐coated films of TTF‐arborols as semiconducting charge‐transport layers in optoelectronic devices. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
Cover Picture: Gold‐Catalyzed Hydroarylation of Alkynes (Eur. J. Org. Chem. 18/2003)
Authors: Reetz Manfred T. , Sommer Knut 
Published: September 2003

AbstractThe cover picture shows the proposed mechanism of the gold(I)‐catalyzed hydroarylation of electron‐poor alkynes. A ligand‐stabilized gold(I) cation reacts with acetylenecarboxylic acid ester to form a π complex in which the alkyne coordinates via its triple bond to the soft and thus carbophilic cationic gold center. This complex is attacked by mesitylene from the side opposite to the bulky gold cation, resulting in the formation of a vinylgold intermediate. The simultaneously released H+ protonates this intermediate stereospecifically, setting free the product (Z)‐β‐mesitylacrylic acid ester as well as regenerating the cationic gold catalyst. Details are discussed in the article by M. T. Reetz and K. Sommer on p. 3485 ff.
‘Greening’ the chemical industry: research and development priorities for biobased industrial products
Authors: Dale Bruce E 
Published: September 2003

AbstractThe chemical industry developed over the past century using petroleum as its primary feedstock. A variety of economic, political and social forces are now leading the chemical industry to use or consider renewable plant‐based feedstocks in addition to or instead of petroleum. The next century may see a gradual transition away from petroleum as the primary feedstock for chemicals, materials and liquid fuels. If this transition is to occur, and if the chemical industry is to become more sustainable, a considerable amount of research must be done. This paper summarizes the research and development priorities for a more sustainable, or ‘green’, chemical industry based on renewable plant resources and relies heavily on a recent report of the National Research Council (NRC) of the United States. Copyright © 2003 Society of Chemical Industry
Breast conservation therapy rates are no different in medically indigent versus insured patients with early stage breast cancer
Authors: Parviz Maryam , Cassel Jay Brian , Kaplan Brian J. , Karp Stephen E. , Neifeld James P. , Penberthy Lynne T. , Bear Harry D. 
Published: September 2003

AbstractPurposeMultiple prospective, randomized studies show that breast conservation therapy (BCT) results in survival rates equal to mastectomy (Mx) for patients with early stage breast cancer (ESBC). Nevertheless, BCT remains underused in certain areas of the nation, without clearly definable reasons. Several studies have implicated socioeconomic status as one potential cause for this disparity in BCT usage. We sought to compare BCT rates in the medically indigent versus insured patients, within the same institution.MethodsData from 1993 to 2000, collected from the institutional tumor registry and the hospital's claims records, were analyzed for 928 patients with ESBC (Stages 0, I, and II), treated at a single medical center. The same surgeons treated both insured and indigent patients. Patients treated by BCT or Mx were compared for age, race, stage, insurance status, access to a radiation therapy center, surgeon, and year of diagnosis.ResultsPatient age, race, surgeon, or insurance status did not significantly affect the rate of mastectomy. Stage I patients (P < 0.001) and those treated after 1995 had higher BCT rates (54.9% in 1993–95 vs. 70.7% in 1996–2000; P < 0.001). Travel distance to a radiation therapy center had no significant impact on BCT rates, except for patients >40 miles distant.ConclusionsThese data refute the hypothesis that socioeconomic status, as reflected by medical insurance, is a determinant of BCT in women with ESBC. Distance of <40 miles to a radiation therapy facility, Stage I disease, and diagnosis after 1995 were factors associated with higher BCT rates. J. Surg. Oncol. 2003;84:57–62. © 2003 Wiley‐Liss, Inc.