merger. Hoechst may be required to di- first efficient regioselective method for vest certain drug lines or businesses to severing two adjacent bonds in C60. They accomplished this using simple meet FTC's market competition concerns, which could result in job elimina- reagents. Qo was first treated with an organic azide to yield an azafulleroid, in tions (C&EN, July 3, page 8). Redundancies within the merged which one carbon-carbon bond has been companies' generic drug operations cleaved and replaced with a nitrogen could also lead to business eliminations bridge. The C=C bonds adjacent to this and employee reductions. Hoechst will nitrogen atom are much more reactive own MMD's U.S. generic drugs unit, than other C=C bonds of QQ, Wudl exRugby Group, which had sales, entire- plains. Taking advantage of this, his ly in the U.S., of $296 million in 1994. group used a reaction with singlet oxygenfirstreported in 1993 by Christopher Rugby employs 770 workers. But Hoechst already owns a 51% S. Foote's group at the University of Calstake in Copley Pharmaceutical, another ifornia, Los Angeles, to cleave one of U.S. generic drugmaker, which had sales these activated C=C bonds, producing of $114 million in 1994. After the merger, an 11-membered ketolactam—a fullerHoechst's generic drugs business would ene with a hole. It was isolated in pure include Rugby; Hoechst's share of Cop- form in about 70% yield. One computer model indicates that ley; and companies in the U.K., South Africa, and Japan—with total sales pro- under ordinary conditions the hole is not large enough to allow a guest moljected at about $540 million. George Peaffecule to enter the cage. Moreover, the hole is partially blocked by a bulky protecting group on the nitrogen atom. "We have not succeeded in taking that blocking group off," Wudl tells C&EN. At higher temperatures, however, Holey buckyball! and carbon arc burning to make That's exactly what a team of chem- fullerene cages that encapsulate atoms the model predicts that the bonds ists at the University of California, San- of certain metals or gases. Unfortunate- around the hole will stretch to make an ta Barbara, has made—a fullerene cage ly, these synthetic methods produce opening about 0.3 x 0.5 A—sufficient to with a hole synthetically punched in it. only very low yields of the host-guest allow a helium atom to pass through. The accomplishment "can be consid- complexes. And separating the stuffed Wudl, collaborating with chemistry ered a first step toward the controlled fullerenes from the hollow ones is a professor Martin Saunders of Yale Uniopening of the fullerene cage," the major headache. Furthermore, the laser versity, is trying to see whether helium UCSB researchers write in last week's and carbon arc methods probably trapped inside the cage will be able to aren't suitable for encapsulating small escape through the opening. Journal of the American Chemical Society In principle, Wudl points out, they [117, 7003 (1995)]. Opening the cage— molecules or molecular and atomic could use the same procedure to make and being able to close it—would allow ions. chemists to trap atoms and molecules Chemists have therefore sought to larger openings. And closing the cage inside the carbon framework, produc- develop synthetic tools for opening also is at hand—but that's all for future ing new materials with potentially use- fullerene cages in a controlled way. The publications. Chemistry professor Amos B. Smith ful properties. UCSB group—consisting of chemistry Since 1991, scientists have learned professor Fred Wudl and visiting scien- III of the University of Pennsylvania how to use "brute force" methods such tists Jan C. Hummelen and Maurizio congratulates Wudl on his accomplishas high-temperature laser vaporization Prato—has succeeded, developing the ment, calling it "an important milestone," one that may finally enable chemists to prepare bulk quantities of fullerene-encapsulated materials. Photooxygenation reaction leads to holey buckyball In a break from the typically polysyllabic, jargon-laden titles of most chemical publications, the UCSB researchers gave their J ACS paper an unusual title: "There Is a Hole in My Bucky." Says Wudl, "We didn't think the editor would let us get away with it, actually." But there was no problem. In fact, says Frederick D. Lewis, the JACS ediAzafulleroid Ketolactam Presumed tor who handled the paper, the referees 1,2-dioxetane thought "it was a clever title for a clevR = methoxyethoxymethyl intermediate er piece of work." Ron Dagani
Hoechst indicates that 1,400 positions in Germany will be eliminated but gives no specifics on the types of positions that will be dropped. It also declines to indicate where the remaining 6,600 jobs will be eliminated. However, the integration of MMD will surely present overlapping operations that likely will be trimmed. Employee reductions are possible within the companies7 combined $1.5 billion R&D operations, as cost savings could be realized by consolidating dual programs. But MMD's 1,500-member sales force likely will remain nearly intact. Hoechst has cited MMD's inroads into the U.S. managed-care market as an incentive in its purchase of the company. Although Hoechst has already acquired Dow Chemical's 71% shareholding in MMD, it is precluded from integrating MMD's operations until after the Federal Trade Commission (FTC) concludes its antitrust investigation of the
Chemists punch hole in fullerene cage
JULY 10,1995 C&EN
9
