Boron-based additives

Kilinc Mert, Cakal Gaye O., Bayram Goknur, Eroglu Inci, and Ozkar Saim. Flame retardancy and mechanical properties of pet-based composites containing phosphorus and boron-based additives. J. Appl. Polym. Sci. 132 no. 22 (2015) 42016-42021. 

Except for the small amounts of boron-based additives in the enhanced matrix, the standard SiCf/SiC and enhanced SiCf/SiC samples are very similar, with the fibre types, volume fractions and architecture being virtually identical. Because the longitudinal fibres control the rates of creep strain accumulation, the initial portions of the creep strain/time curves are therefore indistinguishable. However, the point of... 

Soft magnetic materials are characterized by high permeabiUty and low coercivity. There are sis principal groups of commercially important soft magnetic materials iron and low carbon steels, iron—siUcon alloys, iron—aluminum and iron—aluminum—silicon alloys, nickel—iron alloys, iron-cobalt alloys, and ferrites. In addition, iron-boron-based amorphous soft magnetic alloys are commercially available. Some have properties similar to the best grades of the permalloys whereas others exhibit core losses substantially below those of the oriented siUcon steels. Table 1 summarizes the properties of some of these materials. 

Synthetic resins, such as phenoHc and cresyUc resins (see Phenolic resins), are the most commonly used friction material binders, and are usually modified with drying oils, elastomer, cardanol [37330-39-5] an epoxy, phosphoms- or boron-based compounds, or even combinations of two. They ate prepared by the addition of the appropriate phenol and formaldehyde [50-00-0] in the presence of an acidic or basic catalyst. Polymerization takes place at elevated temperatures. Other resin systems are based on elastomers (see Elastomers, synthetic), drying oils, or combinations of the above or other polymers. 

Boron, oxide additives in silicate-based glasses, x-ray photomission spectroscopic spectra. 151/ Bridges... 

OS 44] ]R 4a] ]P 33] Conventionally, base addition is needed for Suzuki couplings to activate the boronic acid group (Figure 4.68) [6, 7]. 

In addition to being useful reagents for the reductions of carbonyl compounds, boron-based reagents can also be used for the conversion of an alkene to a wide variety of functionalized alkanes. Because the majority of these reagents carry a terpene substituent, they are discussed under these chiral pool materials (Chapter 5). 

Lack of space prevents descriptions of a number of additional types of boron compounds such as the numerous interstitial metallic borides, the subhalides (of type B2CI4), the organoboron compounds (such as B(CH3)3), and the boron-nitrogen addition compounds, many of which have been prepared by H. C. Brown to study the effects of structures on the stability of Lewis acid-base adducts. ... 

Thermally conductive compounds are mainly used in the electronic industry to remove heat from electronic components. Additives to be used are ceramics (e.g., aluminum nitride, or boron nitride) or carbon-based additives (e.g., graphite, carbon Abers, or CNTs) or even metal Abers [63, 64]. The concentrations used are quite high and can easily be in the 50% range. 

Aerobic oxidative Heck reactions also proceed between olefins and other aryl nucleophiles such as aryl tin and aryl boron reagents (Eq. (8.22)). This field started by utilizing aryl tin reagents and electron-deficient alkenes with stoichiometric base additives such as NaOAc [100], but has been significantly improved by... 

An alternative approach to aziridine synthesis involves transfer of a carbenoid species to imines. Jacobsen achieved the first asymmetric aziridination of imines by transfer of copper carbenoids derived from copper bis-oxazohne catalysts and ethyl diazoacetate onto imines, but this process only proceeds with moderate yield and selectivity. Better results have been achieved by addition of ethyl diazoacetate to imines in the presence of enantiopure Lewis acids such as the boron-based catalysts prepared from vaulted biaryls such as VAPOL (4.154) and B(OPh)3. A range of aryl and alkyl N-benzylaldimines, for example (4.155) and (4.156), undergo aziridination to give ds-aziridines with high ee using this procedure. 

X. Sun, H. S. Lee, X.-Q. Yang, J. McBreen, Electrochem. Solid-State Lett. 2002, 5, A248-A251. Using a boron-based anion receptor additive to improve the thermal stability of LiPF(,-based electrolyte for lithium batteries. 

In addition to Ullmann s copper-catalyzed [107] C(spVN bond formations using haloarenes, a remarkable complementary approach was developed by Chan and Lam during the 1990s using boron-based arylating reagents [108, 109). A detailed review by Andrew W. Thomas and Steven V. Ley on these oxidative copper-mediated and copper-catalyzed arylations, as well as their extension to alcohols [108, 110], is to be found in Chapter 4. 

Development of a Neiv N—H Bond Arylation Reaction Catalytic in Copper 139 Table 4.6 Additional boron-based aryl donors. 

I 4 Copper-Catalyzed Arylations of Amines and Alcohols with Boron-Based Arylating Reagents Table 4.7 Additional N—H bond-containing substrates. 

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