A Serendipitous Discovery

An example of a serendipitous discovery in a field related to diazo chemistry is the first in vitro product of a reaction of molecular nitrogen with a transition metal complex (Allen and Senoff, 1965). As discussed in the context of diazo-metal complexes (Zollinger, 1995, Sec. 3.3), the metal —N2 bonds are similar to C —N2 bonds in organic diazo compounds. The paradigm that N2 is (almost) inert in chemical reactions probably explains why it took so long for N2 complexes to be discovered. ... 

In the early 1980s a serendipitous discovery was made when to a mixture of HRP, luminol, and hydrogen peroxide in buffer, firefly luciferin was accidentally added. The light yield of the HRP-catalyzed peroxidation of luminol was greatly enhanced. This remarkable discovery marked the beginning of a very successful analytical tool for immunoassay and all kinds of blotting (protein, DNA, and RNA) applications [16-18],... 

The hard pretzel is said to be a serendipitous discovery made when an apprentice baker left a tray of soft pretzels in the oven overnight. The resulting hard product was liked and started a whole new business. 

Actually, the earliest derivative of a vinylcyclopropane radical cation was a serendipitous discovery. It was formed by an unusual hydrogen shift upon photo-induced electron transfer oxidation of tricyclo[4.1.0.0 ]heptane (26). This result has been questioned on the grounds that the same rearrangement was not observed in a Freon matrix. However, there is no basis for the assumption that radical cation reactions in frozen matrices at cryogenic temperatures should follow the same course as those at room temperature in fluid solution and in the presence of a radical anion, which is potentially a strong base. In several cases, matrix reactions have taken a decidedly different course from those in solution. For example, radiolysis of 8 in a Freon matrix generated the bicyclo[3.2.0]hepta-2,6-diene radical cation (27 ), or caused retro-Diels-Alder cleavage yet, the... 

In recent work a serendipitous discovery showed that strongly acidic chloroaluminate-containing ionic liquids, whether in combination with trialkylam-monium or with dialkylimidzolium cations, are active and selective for the cleavage of aromatic methyl ethers, even at temperatures <40°C. The ionic liquids are consistently better catalyst than AICI3 for this type of reaction 139). 

The penicillins (or penams) were discovered in 1929 by Sir Alexander Fleming, and developed by Florey, Chain, and Abraham at Oxford University. The history of penicillin became a story of legendary proportions, illustrating the case of a serendipitous discovery combined with brilliant development it also marks the beginning of the modern chemotherapy of infectious diseases. 

In clinical investigations, the first observation is often a serendipitous discovery of clinical efficacy, after which the biochemical mechanism of action is discovered... 

The formation of ketonic products when acetylene hexacarbonyl dicobalt is treated with norbornadiene was a serendipitous discovery first reported in 1971 by Pauson and co-workers.1,2 The group were investigating the reaction between acetylene or phenylacetylene hexacarbonyl dicobalt and norbornadiene and found that varying the nature of the solvent changed the major product of the reaction (Scheme 1). 

A serendipitous discovery(6) that [Pt(cod)2] (cod cyclo-octa-1,5-diene) reacted with perfluoropropene to give the diplatinum complex [pt2 y-C(CF3)2 (cod)2], rather than the simple Ti2 adduct [Pt(CF2 CFCF3)(cod)], led to the idea(7) that mononuclear metal-carbene or -carbyne complexes would combine with nucleophilic and co-ordinatively unsaturated metal species (M") ... 

Peroxide Sensitizers. Poly(methylmethacrylate), PMMA, is the first polymer reported to exhibit an increase in refractive index upon irradiation with uv light (41). Irradiation at either 325 nm (Cd laser) or 365 nm (Hg arc) was found to give an index increase of up to 0.3%, and the resolution, determined from gratings, was shown to be at least 5000 lines/mm. Applications to optical waveguides and holographic elements were suggested. This phenomenon was a serendipitous discovery. The PMMA had been intended for use as an inert matrix for reversible photodimerization when its own photosensitivity was uncovered. 

A serendipitous discovery by Tius has been developed into a useful a-methylenecyclopentene annu-lation procedure. In an attempted synthesis of orthoquinones. Tins treated the allenyl alcohols (71), derived from addition of 1-lithio-l-me xyallene to a-silyloxymethylene ketones, with BF3-Et2. The product a-methylenecyclopentenones (72) were obtained in good yield (equation 39). The process can be... 

For the purposes of this review, heterosapphyrins are defined as being sap-phyrin-like macrocycles in which a furan, thiophene, or selenophene subunit serves to replace one or more of the pyrrole rings. Interestingly, like the pentaazasapphyr-ins, this class of macrocycles has its origins in a serendipitous discovery. It occurred during efforts directed toward the synthesis of the heteroatom analogs of corrole. Specifically, as first reported by Johnson and coworkers in 1969, reaction of... 

The other approach, taken by Hoffman-LaRoche, was to attempt to discover a new, chemically unique lead structural type. Considering the sparsity of knowledge and understanding of the chemical processes of the brain, much less their relationship to behavior and mental disease, such an undertaking might have been akin to a search for the Fountain of Youth. In practical terms, such discoveries had been made based on random screening with the expectation of an accidental hit or, less colloquially, a serendipitous discovery. Tests were developed to determine the ability of compounds to... 

Since there is evidence [111] that imidazole drugs differ in their specificity towards different steroidogenic enzymes, these structure-activity studies raise the prospect of developing selective aromatase inhibitors based on the imidazole nucleus. One such drug, a serendipitous discovery, may be an interesting new compound, 4-(5,6,7,8-tetrahydroimidazo[l,5-a]pyridin-5-yl)-benzonitrile (CGS 16949A, (13)) (as the hydrochloride salt), which has been... 

At the end of the 1960s, a new material with exceptional hard magnetic properties (Table 6.7) was prepared samarium-cobalt, SmCoj. Its most outstanding property is its magnetocrystalline anisotropy reported values are in the range (11-20) x 10 J/m (by comparison, Ba ferrite has an anisotropy of 0.33 x 10 J/m, Table 4.15). Rather than being a serendipitous discovery, the successful synthesis of SmCoj was the result of a systematic effort (Strnat, 1988). 

In a serendipitous discovery, Watanabe and coworkers found that a Ti02-Si02 surface could become extremely hydrophilic under UV illumination [114]. The result of this property is that water spreads evenly across the surface (Fig. 20). If the amount of water is relatively small, the water layer becomes very thin and evaporates quickly. If the amount of water is larger, it forms a sheetlike layer that also has high visual... 

The one compound results from a systematic development programme, the other is a serendipitous discovery without any structure optimisation. The spectrum of modern plant protection research cannot be broader. 

The neonicotinoids were not generated through lead-optimisation of natural products, eg. nicotine or epibatidine, but of nitro-substituted ketene aminals, a serendipitous discovery. 

Gun cotton was a serendipitous discovery in about 1846 of Chrisfian Schonbein (1), a Swiss professor of chemistry. He mopped up a spill of nitric and sulfuric acids with his wife s apron and set the washed apron to dry in fiont of the stove. You might say that Schonbein s discovery occurred in a flash because the apron ignited as it dried. Dr. Schonbein had created cellulose nitrate, a modified form of cellulose. This polymer was first made by Braconnot (2) in 1832 but Schonbein s synthesis method (1) could be commercialized. It is shown in Figure 1. The European political environment in which Schonbein made his discovery was one of incessant military conflict and so was highly receptive to a new eiqilosive. Schonbein patented his discovery and allowed it to be commercialized in Austria and England. Unfortunately, cellulose nitrate was so unstable that the last plant making Schonbein s product blew itself up in 1862. 

At this point in the phosphate-grafted PTFE membrane research odyssey, a serendipitous discovery made it possible for us to make a confident... 

Viral Vaccines. The first human vaccine against a viral disease was created in the l790 s through a serendipitous discovery by British physician Edward Jenner. He observed that people previously infected with material from lesions on the udders of cattle (cowpox) became immune to smallpox. Although Jenner was unaware of why cowpox provided immunity to smallpox, scientists later determined that the cowpox virus contains proteins that cross-react with those of smallpox and produce immunity in those exposed to it. The process of immunization became known as vaccination, derived from the Latin word vacca, which means cow. 

Although the ability of certain monoterpenoids such as geraniol [699-702], the a- and /3-ionones [703], dipentene [704] and terpinyl acetate [705] to act as lures for particular species of insects was a serendipitous discovery, it is now apparent that a more fundamental basis for this activity probably exists with... 

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