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records of women who had received implants with those of 3,353 women who had breast-reduction surgery during the same period. The women with breast imWater split with visible plants had a slightly lower rate of conlight and photocatalyst nective tissue disease (29 cases compared with 14), but neither group differed Japanese scientists have discovered that enough from the general population to incopper(I) oxide can catalyze the splitting dicate excess risk, the researchers conof water into H2 and 0 2 in visible light clude. Even such a large study, however, [Chem. Commun., 1998, 357]. "For the has only "a limited ability to detect a modconversion of solar energy directly into est increase in the risk of rare diseases chemical energy, a photocatalyst which such as scleroderma, the disease most ofworks under visible light is indispens- ten implicated in the literature," the reable," says chemist Kazunari Domen, searchers point out. "It is difficult to see professor at Tokyo Institute of Technolo- how epidemiological studies will shed gy. Until now, the photocatalytic split- more light on this vexed issue," write ting of water has been achieved only by Cyrus Cooper and Elaine Dennison of the using UV radiation, note Domen and co- MRC Environmental Epidemiology Unit, workers at the institute and at Nikon Southampton, England, in an accompanyCorp., Sagamihara. "In this work, we ing editorial.^ have shown that a very common material, Cu20, can be used for this purpose," Domen tells C&EN. "The photocatalytic wa- Chiral microscope tip ter splitting on Cu20 powder proceeds without any noticeable decrease in the ac- discriminates between tivity for more than 1,900 hours," the enantiomers team notes. The quantum efficiency of the reaction is low, however. Previous at- By attaching chiral molecules to the probe tempts to split water with a Cu20 elec- tip of an atomic force microscope (AFM), trode in visible light have resulted in the chemists at the University of Cambridge, photodegradation of Cu20. "The observa- England, can differentiate between the tion of water splitting by visible irradiation enantiomers of a different chiral molecule of Cu20 powder is extremely interesting," on a surface [Nature, 391, 566 (1998)]. comments Harry B. Gray, chemistry pro- Their findings suggest that chemical force fessor at California Institute of Technolo- microscopy—a technique that maps chemgy. "But I am puzzled by the difference in ical features with this finding with the results of earlier work chemically modion irradiation of electrodes built from the fied AFM t i p s could be used to same material."^ investigate binding to arrays of molecules generated Breast implant study through combinafinds no link to disease torial chemistry, according to gradin connective tissue uate student RachA study of 7,442 Swedish women who el McKendry, postreceived breast implants between 1964 doctoral associate and 1993 finds them no more likely than Maria-Elena Theowomen without implants to develop clitou, and team connective tissue diseases [Br. Med. J., leaders Trevor Ray316, 417 (1998)]. The study thus joins ment and Chris several other large-scale studies that have Abell. The refailed to identify a clear association be- searchers coat AFM tween breast implants and disease, al- tips with an acylatthough connective tissue diseases are ed phenylglycine among the most commonly cited com- (top) that's been plaints in court cases against breast im- used in chiral high-performance liquid plant manufacturers. Olof Nyrén, associ- chromatography columns. Then they ate professor of medical epidemiology at measure the interactions of the coated Karolinska Institute in Stockholm, and tips with surfaces to which they had athis colleagues compared the hospital tached derivatives of a chiral mandelic
26 FEBRUARY 16, 1998 C&EN
acid (bottom). They find, for example, that the adhesion force between a tip coated with (5>phenylglycine and a surface modified with the R enantiomer of mandelic acid is more than twice that of a surface covered with (5>mandelic acid. "The results show that chemical force microscopy is sufficiently sensitive to permit discrimination between enantiomers of simple chiral molecules," the Cambridge chemists write.^
Heck coupling works with cheap chlorides Chemists at Max Planck Institute for Coal Research, Muhlheim an der Ruhr, Germany, have devised a palladium complex that catalyzes Heck reaction coupling of otherwise little-reactive aryl chlorides [Angew. Chem. Int. Ed, 37, 481 (1998)]. Because chlorides are cheaper than the bromides or iodides usually used, this discovery could lead to extension of Heck coupling of arènes with other arènes or olefins to industrial production. In one demonstration, organic chemistry professor Manfred T. Reetz, graduate student Gunther Lohmer, and technician Renate Schwickardi couple p-chlorotoluene with styrene to get an 85% yield of/Htnethykra?zs-stilbene.^
EDUCATION Grants to fund synthetic organic chemistry Annual grants and fellowships in synthetic organic chemistry have been announced by Bristol-Myers Squibb, Princeton, NJ. This spring, a company committee will choose two universities to get the first grants of $300,000 each, paid out over three years to support leading young investigators, also chosen by the committee. In addition, the company will award fellowships of $35,000 per year for three years to 10 universities, which will choose third- or fourth-year graduate students to receive them. Of the fellowships, $30,000 will be a stipend to the student and $5,000 will go to the thesis director for supplies. The 10 universities may or may not include the two grant-award universities. The company will also invite grant and fellowship holders to annual symposia at its research labs in Princeton or Wallingford, Conn.^
