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Ethers branched aliphatic

Classification Branched aliphatic ether amine Ionic Nature Cationic Empirical C,gH35NO Formula C-2H25CH2OCH2CH2CH2NH2... [Pg.2177]

Fluorosilicones consist of PDMS backbones with some degree of fluoro-aliphatic side chains. The fluorinated group can be trifluoropropyl, nonafluorohexylmethyl, or fluorinated ether side group [78,28,79]. These polymers differ not only in substituent group, but also in the amount of fluoro-substitution relative to PDMS, the overall molecular weight and crosslink density, and the amount of branching. In most commercially available cases, these polymers are addition cure systems and the reactions are those discussed previously for silicone networks. [Pg.550]

Saturated aliphatic 53C—O— 1150-1060 (vs) 1140-900 (s) Two peaks may be observed for branched chain, usually 1140-1110 cm-1. Usually 930-900 cm-1 may be absent for symmetric ethers... [Pg.1016]

Unstabilized enolates react with allylic carbonates in the presence of metalacyclic iridium-phosphoramidite catalysts. Although ketones and aldehydes have not yet been used directly as pronucleophiles with this catalyst system, silyl enol ethers [80] and enamines [81] react with linear allylic carbonates to form, after workup, p-branched, y-8 unsaturated ketones (Scheme 13). Both methods form products in high yield, branched selectivity, and enantioselectivity for a range of cinnamyl and alkyl-substituted allylic carbonates. However, the silyl enol ethers derived from aliphatic ketones reacted in lower yields than enamines derived from the same ketones. [Pg.188]

Aliphatic ethers with branched side chains such as MTBE (methyl t-butyl ether), especially, deactivate enzymes only to a very small degree in incubation experiments for example, the BAL mentioned above has a half-life h/2 of up to 500 h in aqueous-organic two-phase systems (see Fig. 3.1.6) [21]. This may not hold true for a special enzyme/solvent combination under process conditions. When incubated at higher temperatures or even in the presence of the substrate benzaldehyde the deactivation of the enzyme is much higher (see Table 3.1.2)... [Pg.423]

A peak at m/z 30 is good though not conclusive evidence for a straight-chain primary amine. Further decomposition of the first-formed ion from a secondary or tertiary amine leads to a peak at m/z 30, 44, 58, 72,. ... This is a process similar to that described for aliphatic alcohols and ethers above and, similarly, is enhanced by branching at one of the a-carbon atoms ... [Pg.29]

In the indoor environment, many types of products such as crystals, sprays and liquids are applied for active and preventative protection of insects. Insect sprays are particularly popular because they are easy to handle and can be combined with air fresheners. Commonly, the amount of active agents in these products is well below 2%. For example, a commercially available insecticide for indoor use may contain 0.25% tetramethrin, 0.05% D-phenothrin and 1% of the synergist pipero-nyl butoxide. Pyrethroids are also used as active agents in liquid products against furniture beetle. In addition, materials containing natural fibers are often equipped with synthetic pyrethroids as a precaution. Apart from the active ingredients, volatile components such as acetone, aliphatic hydrocarbons, cycloalkanes, branched alkanes C3-benzenes and dipropylene glycol monomethyl ether are usually present in insecticides. [Pg.356]

When some straight and branched-chain aliphatic alcohols, such as n-propanol, n-butanol and isopropanol, are subjected to high temperatures, dehydrogenation products predominate over dehydration (51). Presumably the eliminations take place via a six-membered transition state and are catalyzed by hydrogen halides in the homogeneous phase (52) to produce olefins. On the other hand, gas phase dehydration over solid catalysts is a valuable process for the preparation of olefins and ethers. [Pg.20]

For example, unbranched aliphatic acids with an even number of carbon atoms will be generously represented, while one finds a nearly complete absence of odd-numbered and branched acids. Nature produces an incredible diversity of the most ingeniously constructed cyclic products containing cycloaliphatic, aromatic, or heterocyclic moieties, but such derivatives like aniline or thiophe-nol, as well as plethora of other simple representatives of these classes, are not in the list of naturally occurring substances. Such important types as alkyl halides, nitro compounds, and diazo compounds would be sparsely represented by very rare (if any) examples. Even the simplest compounds like formaldehyde, chloroform, diethyl ether, dioxane, etc., which are trivial to organic chemists, turn to be rather exotic for Nature. In the list of items provided by Nature one will notice the almost complete absence of various organometallic compounds, as well as many other classes of structures of immense scientific and practical significance. [Pg.31]


See other pages where Ethers branched aliphatic is mentioned: [Pg.285]    [Pg.41]    [Pg.1697]    [Pg.224]    [Pg.205]    [Pg.205]    [Pg.11]    [Pg.1691]    [Pg.312]    [Pg.2283]    [Pg.282]    [Pg.161]    [Pg.205]    [Pg.553]    [Pg.143]    [Pg.553]    [Pg.747]    [Pg.204]    [Pg.294]    [Pg.661]    [Pg.82]    [Pg.243]    [Pg.295]    [Pg.133]    [Pg.194]    [Pg.84]    [Pg.456]    [Pg.544]    [Pg.362]    [Pg.544]    [Pg.9]    [Pg.71]    [Pg.187]    [Pg.18]    [Pg.14]    [Pg.704]    [Pg.704]    [Pg.64]    [Pg.94]   
See also in sourсe #XX -- [ Pg.908 ]




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Aliphatic ethers

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