85 Years of Catalysis at Firmenich.

This review relates 85 years of catalysis performed at Firmenich. A special emphasis is shown on how the industry has always focussed on improving the environmental profile of the perfumery ingredients produced and on making them more sustainable. In particular through the application of one of the key principles of Green Chemistry, no. 9, which concerns catalysis. These trends have of course impacted the choice and the need for industrial processes that generate less waste, use less solvent and minimize energy requirements. This review has been organized around key transformations used at Firmenich, and a comparison between stoichiometric and catalytic approaches for some important perfumery ingredients is presented.

Hydrogenation processes in the synthesis of perfumery ingredients.

Homogeneous catalytic hydrogenation has played an important role in the development of modern organic synthesis. Indeed, the discovery of highly regio- and stereoselective catalysts for C=C and C=O bonds reductions has allowed the efficient synthesis of optically active compounds. As the fragrance industry has turned to synthetic ingredients to fulfill the need for novel, cost-effective, and environment-friendly products, the use of catalytic processes are more and more in demand. In this Account, we thus highlight the application of catalytic hydrogenation in the synthesis of fragrance ingredients.

Surface-rolling molecules.

Design, syntheses, and testing of new, fullerene-wheeled single molecular nanomachines, namely, nanocars and nanotrucks, are presented. These nanovehicles are composed of three basic components that include spherical fullerene wheels, freely rotating alkynyl axles, and a molecular chassis. The use of spherical wheels based on C60 and freely rotating axles based on alkynes permits directed nanoscale rolling of the molecular structure on gold surfaces. The rolling motion observed by STM resembles the same motion performed by macroscopic entities in which rolling occurs perpendicular to the axles. A new synthesis methodology, in situ ethynylation of fullerenes, was developed for the realization of the fullerene-wheeled molecular machines. Four generations of the fullerene-wheeled structures were developed, and the latest fourth generation nanocar, 3b, along with three-wheeled triangular compounds, 4a and 4b, provided definitive evidence for fullerene-based wheel-like rolling motion, not stick-slip or sliding translation. The studies here underscore the ability to control directionality of motion in molecular-sized nanostructures through precise molecular design and synthesis.