Ketone ketonization

Li/NH3 (lithium in ammonia) Liquid ammonia -78 -78 to -33 a,P-unsaturated ketone —> ketone ketone — alcohol aldehyde — alcohol aryl ring —> dihydroaryl ring... 

A model for the porphyrin metalation indicates its driving force empty space for the metal ion is provided in the protein-porphyrin complex. Antibody 38C2 efficiently catalyzes a wide variety of ketone-ketone, ketone-aldehyde, aldehyde-ketone, and aldehyde-aldehyde intermolecular cross-aldol reactions. 

Formation of ketones. Ketones can be prepared by the carbonylation of halides and pseudo-halides in the presence of various organometallic compounds of Zn, B, Al, Sn, Si, and Hg, and other carbon nucleophiles, which attack acylpalladium intermediates (transmetallation and reductive elimination). 

Carbon dioxide Enol form of ketone Ketone... 

Polyarylether Ketones. The aromatic polyether ketones are tme thermoplastics. Although several are commercially available, two resins in particular, poly ether ether ketone [31694-16-3] (PEEK) from ICI and poly ether ketone ketone (PEKK) from Du Pont, have received most of the attention. PEEK was first synthesized in 1981 (20) and has been well studied it is the subject of numerous papers because of its potential use in high performance aircraft. Tough, semicrystalline PEEK is prepared by the condensation of bis(4-fiuorophenyl) ketone with the potassium salt of bis(4-hydroxyphenyl) ketone in a diaryl sulfone solvent, such as diphenyl sulfone. The choice of solvent is critical other solvents, such as Hquid HE, promote the reaction but lead to premature low molecular-weight crystals, which do not exhibit sufficient toughness (21). 

Polyether ether ketone ketone (PEEKK), the latest material to be introduced (Hostatec X—Hoechst). 

Scheme 6.7 Synthesis of polyfether ketone ketone) via aromatic electrophilic substitution catalyzed by AICI3.

Scheme 6.18 Synthesis of poly(ketone ketone sulfone) via a polyaminonitrile precursor.

Very few graft copolymers based on poly(arylene ether)s have been synthesized, probably because of their chemical inertness. Klapper et al. reported grafting the polystyrene or polyisoprene onto the poly(ether ether ketone ketone) (PEEKK) by anionic deactivation.229 The carbonyl groups on tire backbone can be attacked by the polystyrene monoanion or polyisoprene anion (Mn about 3000). Due to the steric hindrance only about 30% of tire carbonyl groups can be reacted. 

PEEK precursors, 342 PEEKEK. See Poly(arylene ether ether ketone ether ketone) (PEEKEK) PEEKK. See Poly(ether ether ketone ketone) (PEEKK)... 

Poly(ether ether ketone ketone) (PEEKK), 360, 361... 

This section contains alkylations of ketones and protected ketones, ketone transpositions and annulations, ring expansions and ring openings and dimerizations. Conjugate reductions and Michael alkylations of enone are listed in Section 74 (Alkyls from Alkenes). 

CO 1 0 c 1 X r Nucleophilic substitution and conjugate addition to unsaturated ketones ketones from acyl chlorides b,c... 

THF, ketones, esters, ethylene glycol Aromatic and chlorinated hydrocarbons, MeOH, ketones Ketones, esters... 

This breakdown of fat creates byproducts, chemicals called ketones. Ketones are acidic. Without enough insulin, they begin to build up in the blood. When enough ketones build up, the blood can no longer buffer the acidity. 

It has also been inferred that differences found between crystallinities measured by density and those from heat of fusion by DSC area determination, as given for polyethylenes in the example of Figure 4 [72], may be related to baseline uncertainties, or not accounting for the temperature correction of AHc. Given that similar differences in crystallinity from density and heat of fusion were reported for isotactic poly(propylene) [43] and polyfaryl ether ether ketone ketone), PEEKK [73], other features of phase structure that deviate from the two-phase model may be involved in the crystallinity discrepancy. 

An application involving the use of a polystyrene-immobilized aluminum(III) chloride for a ketone-ketone rearrangement has been presented by Gopalakrishnan and coworkers [144]. 

Ramani, V., Swier, S., Shaw, M. T, Weiss, R. A., Kunz, H. R., and Fenton, J. M. Membranes and MEAs based on sulfonated poly(ether ketone ketone) and heteropolyacids for polymer electrolyte fuel cells. Journal of the Electrochemical Society 2008 155 B532-B537. 

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