NEWS OF THE WEEK NANOCHEMISTRY
HOW TO MAKE THE INSOLUBLESOLUBLE FUNCTIONALIZED Carbon nanotubes with organic appendages are highly soluble.
Attaching large organic groups is key to unclumping nanotubes F ONLY THEY WOULD SWIM
freely in solution, nanotubes might easily realize their enormous potential for electronics and materials. But the chickenwire-like carbon cylinders are notoriously insoluble: They tend to clump together in unmanageable globby ropes. Chemists have tried to address the problem with everything from brute force—where tubes are throttled loose with high-intensi-
ty ultrasound in a process known as sonication—to functionalization with chemical groups that keep the tubesfromassociating. The functionalization approach gets a dramatic boost with new work by organic chemistry professor Maurizio Prato and colleagues at the University of Trieste, in Italy; the University of Notre Dame; and the University of Erlangen-Nurnberg, in Germany The group reports that a method they've developed for attaching organic groups to nanotubes makes the tubes soluble to the tune of50 mgper mL—much higher than previously reported. In addition, the researchers say,
BUSINESS
MERCK PLANS MEDCO SPIN-OFF First drug company into pharmacy benefits to be last one out
M
Gilmartin 12
ERCK & CO. HAS DECIDED
to establish Merck-Medco, its pharmacy benefits management subsidiary, as a separate company Merck acquired Medco in 1993 in an attempt to deal with the managed-care industry's control over drug purchases. Other companies such as Eli Lilly & Co. and SmithKline Beecham subsequently acquired pharmacy benefits management firms of their own, only to sell them a fewyears later at a loss. In contrast, Merck's foray in-
C&EN / FEBRUARY 4, 2002
to the field has been fairly successful. Medco has blossomed under Merck ownership, with revenues growing from $2.2 billion in 1992 to $26 billion by 2001, or about 55% of Merck's total. The company is the leading U.S. pharmacy benefits manager, handling more than 537 million prescriptions annually But "given the evolution of the distinct and highly competitive environments in which Merck andMerck-Medco operate, we believe the best way to enhance the success of both businesses going
the tubes remain in solution in water and a number of organic solvents indefinitely \J. Am. Chem. Soc, 124,760 (2002)}. "IVe never seen {nanotubes} with a solubility as high as this," says chemistry professor James M. Tour at Rice University 'That's really amazing." Several years ago, Prato and his group developed a method that's been widely used to functionalize fullerenes, which they have now extended to nanotubes. This so-called Prato reaction generates reactive azomethine ylides that can attack the nanotubes through the condensation of an a-amino acid and an aldehyde. The nature of the attached groups, which are quite large, is likely key to solubility, as the same reaction done with small organic groups yielded nanotubes that were not very soluble, Prato says. Tour and his group are now trying to replicate the new work, in part for "the joy of saying, 'Voila! We've got it, too.' "-ELIZABETH WILSON
forward is to enable each one to pursue independently its unique and focused strategy," says Merck chairman, president, and CEO Raymond V Gilmartin. The action takes place against the backdrop ofMerck's struggle to rescue an ailing drug business. Merck has warned that earnings growth will stop in 2002. Five of the company's top-selling drugs— accounting for close to one-third of its pharmaceutical sales—face generic competition because all will lose patent protection by June. Selling Medco will make the slowgrowth ofMerck's drug business painfully clear. However, it will leave a more manageable company and may provide funds for future acquisitions. Merck intends to make an initial public offering of Merck-Medco stock by mid2002 and complete the separation of the twofirmswithin the followingyear.-KAREN WATKINS HTTP://PUBS.ACS.ORG/CEN
