Schrock, Nobel prize

The introduction of molybdenum by R. Schrock (Nobel Prize, 2005) and ruthenium catalyst systems by R. Grubbs (Nobel Prize, 2005), especially the commercially available Grubbs catalysP [bis(tricyclohexylphosphine)benzylidene ruthenium(IV) dichloride]. A, and its second-generation variant, B, shown below, " has led to many RCM applications in organic synthesis. ... 

Since the first reports on olefin metathesis in the 1960s [88, 89], this elementary C-C bond forming reaction has sparked an enormous activity in organometalhc research, culminating in the award of the Nobel Prize to Yves Chauvin, Richard Schrock and Robert Grubbs in 2005. 

Metal-catalyzed olefin metathesis had an enormous impact on organic synthesis in general. Extensive research on mechanistic aspects (3,4) and the development of catalysts has been performed, which culminated in the award of the Nobel Prize for Chemistry in 2005 to Chauvin, Grubbs and Schrock. 

Transition-metal-catalysed metathesis of alkenes (Scheme 1.12) is more removed from conventional organic chemistry than the above Michael-like reaction, and its investigation has been a major challenge (see Chapter 12). The novelty and enormous value of these reactions have been recognised by the award of the 2005 Nobel Prize for Chemistry to Chauvin, Schrock and Grubbs for their seminal investigations in this area [28]. 

The 2005 Nobel Prize in Chemistry was awarded to Yves Chauvin (French Petroleum Institute), Robert Grubbs (Caltech), and Richard Schrock (MIT) for developing effective ways to induce alkenes to undergo metathesis. 

In 1980, at age 35, Schrock (Fig. 8.6) was promoted to full professor at MIT and named the Frederick G. Keyes Professor of Chemistry in 1989. He was elected to the American Academy of Arts and Science and the National Academy of Science. Apart from the Nobel Prize, he received inter alia the ACS Award in Organometallic Chemistry, the ACS Award in Inorganic Chemistry, an ACS Arthur C. Cope Scholar Award, and the Sir Geoffrey Wilkinson Medal. In the concluding remarks of his Nobel Lecture [78], he emphasized that he and others have come an enormous distance in the last 30 years, from... 

Fig. 8.6 Richard R. Schrock at the time when he received the Nobel Prize (photo from R. R. S. by courtesy of L. Barry Hetherington)...

R. R. Schrock, Autobiography, in Les Prix Nobel, The Nobel Prizes 2005 (Ed. K. Grandin, [Nobel Foundation], Stockholm, 2006). 

More than half a century ago it was observed that Re207 and Mo or W carbonyls immobilized on alumina or silica could catalyze the metathesis of propylene into ethylene and 2-butene, an equilibrium reaction. The reaction can be driven either way and it is 100% atom efficient. The introduction of metathesis-based industrial processes was considerably faster than the elucidation of the mechanistic fundamentals [103, 104]. Indeed the first process, the Phillips triolefin process (Scheme 5.55) that was used to convert excess propylene into ethylene and 2-butene, was shut down in 1972, one year after Chauvin proposed the mechanism (Scheme 5.54) that earned him the Nobel prize [105]. Starting with a metal carbene species as active catalyst a metallocyclobutane has to be formed. The Fischer-type metal carbenes known at the time did not catalyze the metathesis reaction but further evidence supporting the Chauvin mechanism was published. Once the Schrock-type metal carbenes became known this changed. In 1980 Schrock and coworkers reported tungsten carbene complexes... 

Schrock, Richard R. (1945-). An American Born in Beme, Indiana who won the Nobel Prize for chemistry in 2005 for his pioneering work concerning the development of the metathesis method in organic synthesis. Awarded a B.A. from the University of California, Riverside and a Ph.D. from Harvard University. A member of the American Academy of Arts and Sciences and the National Academy of Sciences. 

Already in this century, six chemists have received the Nobel Prize for seminal work in organometallic chemistry. Noyori, Knowles, and Sharpless became Nobel Laureates in 2001 as a result of their work on the use of organometallic complexes to catalyze asymmetric hydrogenation and oxidation reactions of organic compounds. More details of this work will appear in Chapter 12. Just four years later, Chauvin, Grubbs, and Schrock were honored... 

In 2005, Yves Chauvin, Robert Grubbs, and Richard Schrock were awarded the Nobel Prize in Chemistry for their fundamental studies on the mechanism and applications of metathesis. We will encounter much of their work in the following sections. 

Richard Schrock(MIT, USA) and Robert Grubbs (CalTech, USA) received 2005 Nobel prize for their work on the subject. Metathesis is the exchange of the termination between two alkenes... 

R. R. Schrock, Adv. Synth. Cat., 2007, 349,41 Y. Chauvin, Adv. Synth. Cat., 2008, 349, 27. These Nobel lectures can also be found on the Nobel Prize Web site at http // nobelprize.org/nobel prizes/chemistryAaureates/2005/. 

Organometallic chemistry has been a popular subject for the Nobel prize committee. In 1912 Grignard (Mg) won the award, in 1973 Wilkinson and Fischer for sandwich compounds (such as ferrocene), in 2005 Chauvin, Grubbs, and Schrock for alkene metathesis, and in 2010 Fleck, Negishi, and Suzuki (Stille had died in 1989) for transition-metal catalysed couplings. 

The 2005 Nobel Prize in Chemistry was jointly awarded to Robert H. Grubbs (Caltech), Yves Chauvin (French Petroleum Institute), and Richard R. Schrock (MIT) for establishing olefin metathesis as a reaction of synthetic versatility and contributing to an understanding of the mechanism of this novel process. Olefin metathesis first surfaced in the late 1950s when industrial researchers found that alkenes underwent a novel reaction when passed over a heated bed of mixed metal oxides. Propene, for example, was converted to a mixture of ethylene and 2-butene (cis + trans). 

Tremendous efforts have been put into the development of well-defined single-site transition metal alkylidenes. Mainly the work of R.H. Grubbs and R.R. Schrock (awarded with the Chemistry Nobel Prize 2(X)5, shared with Y. Chauvin) led to the development of well-defined transition metal alkyhdenes that rapidly outrivaled the traditional initiator systems. These initiators have the advantage of being well-defined compounds and in particular of possessing preformed metal alkylidenes (Fig. 3.23). 

---