Web papers

J. Cooper McDonald, George M. Whitesides Poly(dimethylsiloxane) as a Material for Fabricating Microfluidic Devices Acc. Chem. Res. 2002, 35, 491 (YI)
Xiao-Xia Zhu, Marieta Nichifor Polymeric Materials Containing Bile Acids, Acc. Chem. Res. 2002, 35, 539-546 (YI)
Geoffrey W. Coates, Phillip D. Hustad, Stefan Reinartz Catalysts for the Living Insertion Polymerization of Alkenes: Access to New Polyolefin Architectures Using Ziegler-Natta Chemistry Angew. Chem. Int. Ed. 2002, 41, 2236 - 2257 (NT)
Greta R. Patzke, Frank Krumeich, Reinhard Nesper Oxidic Nanotubes and Nanorods - Anisotropic Modules for a Future Nanotechnology Angew. Chem. Int. Ed. 2002, 41, 2446-2461 (NT)
Alexander Star, David W. Steuerman, James R. Heath, J. Fraser Stoddart Starched Carbon Nanotubes Angew. Chem. Int. Ed. 2002, 41, 2508-2512 (NT)
Simon Harrisson, Jonathan P. Rourke, David M. Haddleton, 13C Kinetic isotope effects in the copper(I)-mediated living radical polymerization of methyl methacrylate Chemical Communications, 14, 1470, 2002 (ML)
Joseph G. Cordaro, James K. McCusker, Robert G. Bergman, Synthesis of mono-substituted 2,2 -bipyridines Chemical Communications, 14, 1496, 2002 (ML)
Rob van de Coevering, Mark Kuil, Robertus J. M. Klein Gebbink, Gerard van Koten, A polycationic dendrimer as noncovalent support for anionic organometallic complexes Chemical Communications, 15, 1636, 2002 (ML)
Shu-Hong Yu, Helmut Colfen, Markus Antonietti Control of the Morphogenesis of Barium Chromate by Using Double-Hydrophilic Block Copolymers (DHBCs) as Crystal Growth Modifiers Chem. Eur. J. 2002, 8, No. 13 2937-2945 (NT)
Gregory S. Owens, Armando Durazo, Mahdi M. Abu-Omar Kinetics of MTO-Catalyzed Olefin Epoxidation in Ambient Temperature Ionic Liquids: UV/Vis and 2H NMR Study Chem. Eur. J. 2002, 8, No. 13 3053-3059 (NT)
Zhibin Guan Control of Polymer Topology by Chain-Walking Catalysts Chem. Eur. J. 2002, 8, No. 13 3086-3092 (NT)
Xian-Ming Zhang, Ming-Liang Tong, Meng-Lian Gong, Hung-Kay Lee, Li Luo, King-Fai Li, Ye-Xiang Tong, Xiao-Ming. Syntheses, Crystal Structures, and Physical Properties of Dinuclear Copper(I) and Tetranuclear Mixed-Valence Copper(I,II) Complexes with Hydroxylated Bipyridyl-Like Ligands Chem. Eur. J. 2002, 8, No. 13 3187-3194 (NT)
Qingzhi Zhang, Stephen M. Aucott, Alexandra M. Z. Slawin, J. Derek Woollins Synthesis and Coordination Chemistry of the New Unsymmetrical Ligand Ph2PCH2NHC6H4PPh2 Eur. J. Inorg. Chem. 2002, 1545-1556 (TP)
Éva Balogh-Hergovich, Zoltán Gréczi, József Kaizer, Gábor Speier, Marius Réglier, Michel Giorgi, László Párkányi Kinetics and Mechanism of the Copper-Catalysed Oxygenation of 2-Nitropropane Eur. J. Inorg. Chem. 2002, 1687-1696 (TP)
Reto Dorta, Linda J. W. Shimon, Haim Rozenberg, David Milstein. A Facile Oxidative Addition of C-Cl Bonds to New Neutral and Cationic Rhodium(I)-Bipyridine Complexes Eur. J. Inorg. Chem. 2002 1827-1834 (TP)
Jin-Ying Yuan and Cai-Yuan Pan, "Living" free radical ring-opening copolymerization of 4,7-dimethyl-2-methylene-1,3-dioxepane and conventional vinyl monomers, European Polymer Journal, 38 (10), 2069, 2002 (ML)
Bao-Hui Xia, Chi-Ming Che, David Lee Phillips, King-Hung Leung, and Kung-Kai Cheung Natarajan Metal-Metal Interactions in Dinuclear d8 Metal Cyanide Complexes Supported by Phosphine Ligands. Spectroscopic Properties and ab Initio Calculations of [M2(-diphosphine)2(CN)4] and trans-[M(phosphine)2(CN)2] (M = Pt, Ni) Inorg. Chem. 2002, 41, 3866-3875 (TP)
Lachelle Arnt and Gregory N. Tew New Poly(phenyleneethynylene)s with Cationic, Facially Amphiphilic Structures. J. AM. CHEM. SOC. 9 VOL. 124, NO. 26, 2002 (LB)
Jinsang Kim, Igor A. Levitsky, D. Tyler McQuade, and Timothy M. Swager, Structural Control in Thin Layers of Poly( p-phenyleneethynylene)s: Photophysical Studies of Langmuir and Langmuir-Blodgett Films. J. AM. CHEM. SOC. 9 VOL. 124, NO. 26, 2002.p 7712 (LB)
Thierry Cassagneau and Frank Caruso Oligosilsesquioxanes as Versatile Building Blocks for the Preparation of Self-Assembled Thin Films..J. AM. CHEM. SOC. 2002, 124, 8172-8180 (LB)
Ryo Yoshida, Takamasa Sakai, Shoji Ito, and Tomohiko Yamaguchi.. Self-Oscillation of Polymer Chains with Rhythmical Soluble-Insoluble Changes. .J. AM. CHEM. SOC. 2002, 124, 8095-8098 (LB)
Gary P. Harp, Keshav S. Gautam, and Ali Dhinojwala. Probing Polymer/Polymer Interfaces. .J. AM. CHEM. SOC. 2002, 124, 7908-7909 (LB)
Michael J. Zacuto, Steven J. O'Malley, and James L. Leighton. Tandem Intramolecular Silylformylation-Crotylsilylation: Highly Efficient Synthesis of Polyketide Fragments. J. AM. CHEM. SOC. 2002, 124, 7890-7891 (LB)
Makoto Mitani, Rieko Furuyama, Jun-ichi Mohri, Junji Saito, Seiichi Ishii, Hiroshi Terao,Norio Kashiwa, and Terunori Fujita Fluorine- and Trimethylsilyl-Containing Phenoxy-Imine Ti Complex for Highly Syndiotactic Living Polypropylenes with Extremely High Melting Temperatures. J. AM. CHEM. SOC. 2002, 124, 7888-7889 (LB)
Svetlana A. Burova and Frank E. McDonald. Stereoselective Synthesis of a Family of Alternating Polyols from Six-Carbon Epoxyalkynol Modules. J. AM. CHEM. SOC. 2002, 124, 8188-8189. (LB)
Tomislav Pintauer, Peng Zhou, and Krzysztof Matyjaszewski General Method for Determination of the Activation, Deactivation, and Initiation Rate Constants in Transition Metal-Catalyzed Atom Transfer Radical Processes. J. AM. CHEM. SOC. 2002, 124, 8196-8197. (LB)
Yanhou Geng, Anita Trajkovska, Dimitris Katsis, Jane J. Ou, Sean W. Culligan, and Shaw H. Chen, Synthesis, Characterization, and Optical Properties of Monodisperse Chiral Oligofluorenes . .J. AM. CHEM. SOC. 2002, 124, 8337-8347. (LB)
Daniel J. Duffy, Kanad Das,Shaw L. Hsu, Jacques Penelle,Vincent M. Rotello, and Howard D. Stidham. Binding Efficiency and Transport Properties of Molecularly Imprinted Polymer Thin Films. J. AM. CHEM. SOC. 2002, 124, 8290-8296. (LB)
Jessica L. Bender, Perry S. Corbin, Cassandra L. Fraser, David H. Metcalf, Frederick S. Richardson, Edwin L. Thomas, and Augustine M. Urbas. Site-Isolated Luminescent Europium Complexes with Polyester Macroligands: Metal-Centered Heteroarm Stars and Nanoscale Assemblies with Labile Block Junctions..J. AM. CHEM. SOC. 2002, 124, 8526-8527. (LB)
Eva Harth, Brooke Van Horn, Victor Y. Lee, David S. Germack, Chad P. Gonzales,Robert D. Miller, and Craig J. Hawker A Facile Approach to Architecturally Defined Nanoparticles via Intramolecular Chain Collapse. J. AM. CHEM. SOC. 2002, 124, 8653-8660. (LB)
Harold W. Boone, Phillip S. Athey, Michael J. Mullins, Dean Philipp, Richard Muller, and William A. Goddard. Copolymerization Studies of Vinyl Chloride and Vinyl Acetate with Ethylene Using a Transition-Metal Catalyst. .J. AM. CHEM. SOC. 2002, 124, 8790-8791. (LB)
Laia Crespo, Gloria Sanclimens, Beatriz Montaner, Ricardo Perez-Tomas, Miriam Royo, Miquel Pons, Fernando Albericio, and Ernest Giralt, Peptide Dendrimers Based on Polyproline Helices. J. AM. CHEM. SOC. 2002, 124, 8876-8883. (LB)
Francis P. Zamborini, Michael C. Leopold, Jocelyn F. Hicks, Pawel J. Kulesza, Marcin A. Malik, and Royce W. Murray Electron Hopping Conductivity and Vapor Sensing Properties of Flexible Network Polymer Films of Metal Nanoparticles J. AM. CHEM. SOC. 2002, 124, 8958-8964. (LB)
George T. Wang, Collin Mui, Charles B. Musgrave, and Stacey F. Bent,. Competition and Selectivity of Organic Reactions on Semiconductor Surfaces: Reaction of Unsaturated Ketones on Si(100)-2-1 and Ge(100)-2-1..J. AM. CHEM. SOC. 2002, 124, 8990-9004. (LB)
Akikazu Matsumoto, Toshihiro Tanaka, Takashi Tsubouchi, Kohji Tashiro, Seishi Saragai, and Shinsuke Nakamoto. Crystal Engineering for Topochemical Polymerization of Muconic Esters Using Halogen-Halogen and CH/ð Interactions as Weak Intermolecular Interactions. J. AM. CHEM. SOC. 2002, 124, 8891-8902. (LB)
Stephen T. Balke, Thomas H. Mourey, Douglas R. Robello, Tammy A. Davis, Alexander Kraus, Krzysztof Skonieczny,. Quantitative analysis of star-branched polymers by multidetector size-exclusion chromatography Journal of Apllied Polymer Science Volume 85, Issue 3, 2002, 552-570 (JFL)
J. Kadokawa ; K. Ikuma ; H. Tagaya Polymerization Of Acrylate Monomer Containing Two Hydroxy Groups Initiated With Sodium Hydride For Synthesis Of Hyperbranched Polymer JMSPA, 2002, Volume 39, Issue 8, 879 - 888 (TL)
Koichi Hatada ; Tatsuki Kitayama ; Nobutaka Fujimoto ; Tetsuya Fukuoka ; Osamu Nakagawa ; Takafumi Nishiura Preparation Of Star-Shaped Polymer With Stereoregular Poly(Methyl Methacrylate) Arms JMSPA, 2002, Volume 39, Issue 8, 801 - 814 (TL)
Deng Jianping ; Yang Wantai ; Bengt Rånby Surface Photografting Polymerization Of Styrene On Ldpe Film JMSPA, 2002, Volume 39, Issue 8, 771-786 (TL)
Mark C. McCairn, Stephen R. Tonge, and Andrew J. Sutherland Synthesis and Evaluation of Poly(oxyethylene glycol) Polymer (POP) Supports JOC,2002, 67,14, 4847-4855 (TL)
Shun-Ichi Murahashi Palladium-catalyzed cross-coupling reaction of organic halides with Grignard reagents, organolithium compounds and heteroatom nucleophiles Journal of Organometallic Chemistry 653 (2002) 27-33 (CT)
Joseph Jagur-Grodzinski, Johannes Smid,. Michael Szwarc, 1909-2000, Journal of Polymer Science Part A Volume 40, Issue 13, 2002. Special Issue: Dedicated to the Memory of Professor Michael Szwarc 2099-2100 (JFL)
Kyung-Youl Baek, Masami Kamigaito, Mitsuo Sawamoto, Star-shaped polymers by Ru(II)-catalyzed living radical polymerization. II. Effective reaction conditions and characterization by multi-angle laser light scattering/size exclusion chromatography and small-angle X-ray scattering Journal of Polymer Science Part A Volume 40, Issue 14, 2002, 2245-2255 (JFL)
Auke Snijder, Bert Klumperman, Rob Van Der Linde, End-group modification of poly(butyl acrylate) prepared by atom transfer radical polymerization: Mechanistic study using gradient polymer elution chromatography Journal of Polymer Science Part A Volume 40, Issue 14, 2002, 2350-2359 (JFL)
Yoshikatsu Suito, Yutaka Isobe, Shigeki Habaue, Yoshio Okamoto, Isotactic-specific radical polymerization of methacrylamides in the presence of Lewis acids Journal of Polymer Science Part A Volume 40, Issue 14, 2002, 2496-2500 (JFL)
Auke Snijder, Bert Klumperman, Rob Van Der Linde. End-group modification of poly(butyl acrylate) prepared by atom transfer radical polymerization: Mechanistic study using gradient polymer elution chromatography Journal of Polymer Science Part A Volume 40, Issue 14, 2350-2359 2002 (JFL)
Jyongsik Jang and Hyunkyou Ha Fabrication of Hollow Polystyrene Nanospheres in Microemulsion Polymerization Using Triblock Copolymers Langmuir 2002, 18, 5613-5618 (YI)
Hyeon Suk Shin, Young Mee Jung, Tae Young Oh, Taihyun Chang, Seung Bin Kim, Do Hyung Lee, and Isao Noda Glass Transition Temperature and Conformational Changes of Poly(methyl methacrylate) Thin Films Determined by a Two-Dimensional Map Representation of Temperature-Dependent Reflection-Absorption FTIR Spectra Langmuir 2002, 18, 5953-5958 (YI)
Yining Lin, Thomas W. Smith, and Paschalis Alexandridis, Adsorption of a Rake-Type Siloxane Surfactant onto Carbon Black Nanoparticles Dispersed in Aqueous Media Langmuir 2002, 18, 6147-6158 (YI)
C. Mengel, A. R. Esker, W. H. Meyer, and G. Wegner. Preparation and Modification of Poly(methacrylic acid) and Poly(acrylic acid) Multilayers Langmuir 2002, 18, 6365-6372 (YI)
Lei Ying, E. T. Kang, and K. G. Neoh. Synthesis and Characterization of poly(N-isopropylacrylamide)-graft-Poly(vinylidene fluoride) Copolymers and Temperature-Sensitive Membranes Langmuir 2002, 18, 6416-6423 (YI)
Mukundan Chakrapani, David H. Van Winkle, Brian C. Patterson, and Randolph L. Rill Acrylamide Polymerized in the Presence of Surfactants: Surface Analysis Using Atomic Force Microscopy Langmuir 2002, 18, 6449-6452 (YI)
A. Cherfi, G. Févotte, On-line conversion monitoring of the solution polymerization of methyl methacrylate using near-infrared spectroscopy Macromol Chem. Phys.Volume 203, Issue 9, 2002 1188-1193 (JFL)
David Jacques, Mickael Minot, Terry Rantell Fabrication of Carbon Multiwall Nanotube/Polymer Composites by Shear Mixing Rodney Andrews, Macromolecular Materials and Engineering/ Volume 287, Issue 6, 395-403 2002 (DN) Abstract PDF Full Tex
K. Nicole Power-Billard, Ian Manners Water-Soluble Block Copolymers with an Organometallic Polyferrocenylsilane Polyelectrolyte Block via a Sequential Anionic Transition Metal-Catalyzed Polymerization Approach Macromol. Rapid Commun. 23(10-11) 607-611 (2002) (AN)
A. Ramakrishnan, R. Dhamodharan, Jürgen Rühe Controlled Growth of PMMA Brushes on Silicon Surfaces at Room Temperature Macromol. Rapid Commun. 23(10-11) 612-616 (2002) (AN)
Qi Wang, Huaxiang Yang, Zhiqiang Fan Efficient Activators for an Iron Catalyst in the Polymerization of Ethylene Macromol. Rapid Commun . 23(10-11) 639-642 (2002) (AN)
Georgia Papavasiliou, Inan Birol, Fouad Teymou. Calculation of Molecular Weight Distributions in Non-Linear Free-Radical Polymerization Using the Numerical Fractionation Technique Macromol. Theory Simul. 2002, 11, 533 548 (YI)
Jie Feng, Honglai Liu, Ying Hu Microdomain Morphology of Symmetrical Diblock Copolymer Thin Films Confined in a Slit Macromol. Theory Simul. 2002, 11, 549-555 (YI)
Jie Feng, Honglai Liu, Ying Hu Asymmetric Diblock Copolymer Thin Film Confined in a Slit: Microphase Separation and Morphology Macromol. Theory Simul. 2002, 11, 556-565 (YI)
Jie Feng, Eli Ruckenstein The Morphology of Symmetric Triblock Copolymer Melts Confined in a Slit: A Monte Carlo Simulation Macromol. Theory Simul. 2002, 11, 630-639 (YI)
Cokki Versluis, Tom Hillegers . On the Contraction Factor of Star-Branched Polymers with Flory-Distributed Arms Macromol. Theory Simul. 2002, 11, 640 648 (YI)
Michael S. Donovan, Taylor A. Sanford, Andrew B. Lowe, Brent S. Sumerlin, Yoshiro Mitsukami, and Charles L. McCormick RAFT Polymerization of N,N-Dimethylacrylamide in Water Macromolecules 2002, 35, 4570-4572 (TS)
Galina I. Litvinenko and Axel H. E. Muller Molecular Weight Averages and Degree of Branching in Self-Condensing Vinyl Copolymerization in the Presence of Multifunctional Initiators Macromolecules 2002, 35, 4577-4583 (TS)
Auke Snijder, Bert Klumperman, and Rob van der Linde Kinetics of Heterogeneous Atom Transfer Radical Polymerization of Methyl Methacrylate Macromolecules 2002, 35, 4785-4790 (TS)
Mical E. Honigfort, William J. Brittain, Todd Bosanac and Craig S. Wilcox Use of Precipitons for Copper Removal in Atom Transfer Radical Polymerization Macromolecules, 2000, 35, 4849-4851. (TS)
Xiao-Shuang Feng and Cai-Yuan Pan. Synthesis of Amphiphilic Miktoarm ABC Star Copolymers by RAFT Mechanism Using Maleic Anhydride as Linking Agent Macromolecules 2002, 35, 4888-4893 (TS)
J. J. Vosloo, D. De Wet-Roos, M. P. Tonge, and R. D. Sanderson Controlled Free Radical Polymerization in Water-Borne Dispersion Using Reversible Addition-Fragmentation Chain Transfer Macromolecules 2002, 35, 4894-4902 (TS)
Celine Farcet, Joel Belleney, Bernadette Charleux, and Rosangela Pirri Structural Characterization of Nitroxide-Terminated Poly(n-butyl acrylate) Prepared in Bulk and Miniemulsion Polymerizations Macromolecules 2002, 35, 4912-4918. (TS)
Stephen G. Boyes, William J. Brittain, Xin Weng, and Stephen Z. D. Cheng. Synthesis, Characterization, and Properties of ABA Type Triblock Copolymer Brushes of Styrene and Methyl Acrylate Prepared by Atom Transfer Radical Polymerization Macromolecules 2002, 35, 4960-4967 (TS)
Jong-Bum Kim, Wenxi Huang, Merlin L. Bruening, and Gregory L. Baker. Synthesis of Triblock Copolymer Brushes by Surface-Initiated Atom Transfer Radical Polymerization Macromolecules 2002, 35, 5410-5416 (TS)
Stuart W. Prescott, Mathew J. Ballard, Ezio Rizzardo, and Robert G. Gilbert Successful Use of RAFT Techniques in Seeded Emulsion Polymerization of Styrene: Living Character, RAFT Agent Transport, and Rate of Polymerization Macromolecules 2002, 35, 5417-5425 (TS)
Andrea M. Kasko, Steven R. Grunwald, and Coleen Pug. Effect of End Groups on the Thermotropic Behavior of Linear Poly[11-(4'-cyanophenyl-4'-phenoxy)undecyl acrylate]s Prepared by ATRP and Their Topological Blends Macromolecules 2002, 35, 5466-5474 (TS)
K. Tsolakis, J. K. Kallitsis, A. Godt. Synthesis of Luminescent Rod-Coil Block Copolymers Using Atom Transfer Radical Polymerization Macromolecules 2002, 35, 5758-5762 (TS)
Chiaki Yoshikawa, Atsushi Goto, and Takeshi Fukuda Quantitative Comparison of Theory and Experiment on Living Radical Polymerization Kinetics. 1. Nitroxide-Mediated Polymerization Macromolecules 2002, 35, 5801-5807 (TS)
Shinpei Yamamoto, Yoshinobu Tsujii, and Takeshi Fukuda. Glass Transition Temperatures of High-Density Poly(methyl methacrylate) Brushes Macromolecules 2002, 35, 6077-6079 (TS)
Nicolay V. Tsarevsky, Traian Sarbu, Bernd Gobelt, and Krzysztof Matyjaszewski. Synthesis of Styrene-Acrylonitrile Copolymers and Related Block Copolymers by Atom Transfer Radical Polymerization Macromolecules 2002, 35, 6142-6148 (TS)
Marco Apostolo, Vincenzo Arcella, Giuseppe Storti, and Massimo Morbidelli Free Radical Controlled Polymerization of Fluorinated Copolymers Produced in Microemulsion Macromolecules 2002, 35, 6154-6166 (TS)
Jerome Gromada and Krzysztof Matyjaszewski. Measurement of Initial Degree of Polymerization without Reactivation as a New Method To Estimate Rate Constants of Deactivation in ATRP Macromolecules 2002, 35, 6167-6173 (TS)
Hongsui Sun, Vladimir V. Burlakov, Anke Spannenberg, Wolfgang Baumann, Perdita Arndt, and Uwe Rosenthal. Reactions of Zirconocene-Alkyne Complexes with Polar Functionalized Olefins Organometallics 2002, 21, 3360-3366 (TP)
Sam Bradley, Kenneth D. Camm, Stephen J. Furtado, Andrew L. Gott, Patrick C. McGowan, Thomas J. Podesta, and Mark Thornton-Pett Synthesis and Structure of Amino-Functionalized Cyclopentadienyl Vanadium Complexes and Evaluation of Their Butadiene Polymerization Behavior Organometallics 2002, 21, 3443-3453 (TP)
Weijun Liu, Jon M. Malinoski, and Maurice Brookhart. Ethylene Polymerization and Ethylene/Methyl 10-Undecenoate Copolymerization Using Nickel(II) and Palladium(II) Complexes Derived from a Bulky P,O Chelating Ligand Organometallics 2002, 21, 2836-2838 (TS)
J. Habsuda, G. P. Simon, Y. B. Cheng, D. G. Hewitt, D. A. Lewis and H. Toh, Organic-inorganic hybrids derived from 2-hydroxyethylmethacrylate and (3-methacryloyloxypropyl)trimethoxysilane, Polymer, 43, 4123-4136 (2002).(AN)
G. Z. Li, L. Wang, H. Toghiani, T. L. Daulton and C. U. Pittman, Jr. Viscoelastic and mechanical properties of vinyl ester (VE)/multifunctional polyhedral oligomeric silsesquioxane (POSS) nanocomposites and multifunctional POSS-styrene copolymers, Polymer, 43, 4167-4176 (2002). (AN)
Akinori Toyota, Toshiyuki Tsutsui, Norio Kashiwa: Synthesis of terminally functionalized polyolefines Polymer Bulletin 48 (2002) 3, 213-219 (NT)
F. Moustafa, Zheng Fang, J. P. Kennedy: Novel Polyisobutylene Stars. XXVIII. A star block comprising three poly (isobutylene-b-acrylonitrile) arms radiating from an aromatic core: Synthesis and characterization Polymer Bulletin 48 (2002) 3, 225-232 (NT)
Barros, M. Teresa; Siñeriz, Fernando Syntheses of Optically Active Monomers and Copolymers Derived from Protected 6'-O-Acryloyl Sucroses Synthesis Issue 10, 2002 1407 (NJ)
Carlo and Miguel Yus, Cecilia Gómez and Pablo Candela Polyphenylene as an electron transfer catalyst in lithiation processes Tetrahedron 58 (2002) 6207-6210 (CT)
Vasudevan V. Namboodiri and Rajender S. Varma, An improved preparation of 1,3-dialkylimidazolium tetrafluoroborate ionic liquids using microwaves, Tetrahedron Letters, 43 (2002), 5381-5383 (MCI)