Fine Chemicals

This week's cover story is C&EN's annual feature on fine chemicals and intermediates. The focus of the three stories that make up the feature is new technologies that enhance process chemistry (see pages 43, 54, and 63).

The stories are significant not only for the science and technology discussed in them, which I will return to shortly, but also because they represent a major change at C&EN. The fine and custom chemicals beat is a critical one for C&EN, anchored by four cover stories each year that are featured on our Editorial Calendar: "Custom Chemicals," "Fine Chemicals & Intermediates," "Chiral Chemistry," and "Pharmaceuticals."

The fine and custom chemicals beat was handled with great skill for many years by now retired senior editor Stephen Stinson. When Stinson retired in 2001, A. Maureen Rouhi, then a senior correspondent, took over the beat and has, for the past four years, handled it brilliantly. Late last year, Rouhi took on management responsibilities at C&EN, becoming deputy assistant managing editor for science, technology, and education coverage, and turned over the fine and custom chemicals beat to Thayer, who was just returning to C&EN after a year as editor of Modern Drug Discovery.

Both Rouhi and Thayer attended last year's Conference on Pharmaceutical Ingredients (CPhI) and this year's Informex trade shows, and Rouhi wrote the Jan. 17, 2005, "Custom Chemicals" cover story. With this week's cover story, the handoff to Thayer is complete.

The three stories in this week's issue focus on technology. In the first, Thayer looks at the use of microreactors to replace batch processes in the synthesis of fine chemicals and intermediates. Microreactor technology, Thayer writes, "employs a system of often miniaturized reactors, mixers, heat exchangers, and other processing elements with internal structures on a micrometer scale. ... Continuous processing based on flow chemistry alone is one advantage. But because of the small channel sizes and high surface area-to-volume ratios, these devices are orders of magnitude more efficient than large-scale batch reactors in heat and mass transfer."

Not every reaction can be run in microreactors, but researchers at a large number of fine chemicals companies are exploring their potential. "All the huge companies involved in chemistry and pharmaceutical chemistry are doing something in microreaction technology," one observer states.

The second story looks at the use of high-throughput experimentation and parallel approaches for exploring synthetic routes and optimizing safe and cost-effective reaction conditions. Some of the approaches used in combinatorial chemistry for drug discovery--which many consider to have been a disappointment--are being harnessed to optimize manufacturing routes.

"High-throughput experimentation frequently is employed when statistical approaches to experimentation trump chemical intuition," Thayer writes. "Examples that researchers offer include repetitive screening for appropriate ion-exchange resins, absorbents to remove impurities, or crystallization conditions."

The third story focuses on the Food & Drug Administration's push for the use of process analytical technology to be incorporated into its broader initiative on current Good Manufacturing Processes (cGMP). The idea, Thayer writes, is that the quality of drugs should not be ensured by testing after the drugs have been manufactured, but should be built into the processes that create the drugs. While the idea seems like a reasonable one, it goes against a long history of drug manufacturing, and its implementation will be complex.

When you read these fascinating stories, I know you'll agree that C&EN's coverage of fine and custom chemicals remains in excellent hands.

Thanks for reading.