Elimination reactivity

Fig. 13.6 Preprocessing compound files. Representative substructural exclusion criteria and compound filters used to prune the CRCD database are shown. These were designed to eliminate reactive compounds, toxic materials, and so on. The complete list of exclusion criteria was developed over a number of years in close collaboration with experienced medicinal chemists.

Among more recent innovations, the alkylative metallacyclobutane and metallacyclobutene synthesis, involving central carbon addition and addition/elimination reactivity patterns, holds considerable promise for near-term synthetic developments (Section 2.12.12). This is equally true in both the nucleophilic and free radical versions of this process, for both catalytic and stoichiometric transformations and multistep reaction cascades. 

Eliminate reactive functional groups, promiscuous inhibitors, and ... 

The use of fingerprints which indicate the presence or absence of functional groups can be very beneficial when eliminating reactive molecules or identifying required functional groups in active molecules. Consequently, it is desirable to store this information in a database in such a way as it can readily be viewed in a spreadsheet. It is not usually feasible to store the similarity of all pairs of molecules which have been synthesised yet alone all those that have been thought about. Good spreadsheet software should be able to compute and display such information on-the-fly. 

Scheme 7.8 General synthetic strategy for incorporating metal-metal bonds into polymer backbones using oxidation or reduction and salt elimination reactivity. See text for details about the oxidation and reduction reactions and about the salt elimination reactions.

Everything in the battery when new is still contained in it when completely discharged. Incineration, pyrometallurgical and hydrolysis methods eliminate reactivity but in many situations ultimately generate a hazardous waste. This may be wastewater, sludge, bag house waste, or ash. 

The C-O reductive elimination chemistry of high valent metal species discovered and matured over the last four decades is being actively explored now. The goals of this Chapter are to overview the C-O bond elimination reactivity of organoplatinum and organopalladium complexes with the metal in an oxidation state greater than - -2 and to discuss the C-O reductive elimination mechanisms involving these complexes. 

Keshavarzian A, Haydek J, Zabihi R et al. Agents capable of eliminating reactive oxygen species. Catalase, WR-2721, or Cu(ll)2(3,5-DlPS)4 decrease experimental colitis. Dig Dis Sci 1992 37 1866-73. 

Note 3 It is weU known that the presence of peroxyl and alkoxyl radicals as well as their DMPO spin adducts in water solutions leads mostly to the formation of OH radicals generating the signal of DMPO-OH adduct. Arbutin is probably able to eliminate reactive alkoxy and peroxyl radieals before their spin trapping. 

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