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Aqueous adds

Raphael has deyised a commercial synthesis using intermediates 365A and B to provide the two halves of the molecule. B is converted in aqueous add to an isomeric alcohol. Draw this. [Pg.117]

The distillation residue (8-9 g) consists of water-soluble oligomers that can be saponified without loss of optical purity by heating at reflux with aqueous add for 15 hr. [Pg.22]

A is an anchor compound, one whose ionization ratios are measurable in dilute aqueous add pAbh+ = 100 for p-nitroaniline is used for H0.22 23 Equation (9) is known as the cancellation assumption using it on a series of overlapping weak base indicators of similar type (primary aromatic amines in the case of Ho) leads to Ho values covering a wide addity range according to equation (8), once all the P bh+ values are known. [Pg.4]

Incorporation Into a co- or terpolymer of a d1ol containing monomer such as solketal acrylate (SA, H, a comonomer readily hydrolyzed by aqueous add to a diol) likewise Increases crosslinking (Scheme 4). Such polymers exhibit Improved dry, wet and solvent resistance (Table V). Alternatively, half of the ABDA comonomer can be substituted with SA, without significantly degrading properties vs the Initial ABDA only sample. [Pg.474]

Care must be taken not to expose product 3 to aqueous add conditions for prolonged periods of time since ring opening of the OBO will occur. Thus care must be taken upon both addition of BFj-EtjO to 2 and upon work-up, hence the sodium bicarbonate wash after the 3% NH4CI extraction. The diol that is formed upon acid-catalyzed hydrolysis of the OBO also crystallizes out making purification of the desired product 3 impossible. [Pg.258]

TABLE 8.4 Indicators for Aqueous Add-base Titrations (continued.)... [Pg.858]

Nishiguchi, T. Hayakawa, S. Hirasaka, Y. Saitoh, M. Selective monotetrahydropyranylation of l,n-diols catalyzed by aqueous adds. Tetrahedron Lett. 2000, 41, 9843-9846. [Pg.352]

When the reaction is worked up with aqueous add, not only is the alkoxide group This Grignard reagent reacts... [Pg.779]

Distillate. This will contain the steam-volatile acidic and neutral components present. Render alkaline with 10-20 per cent NaOH and distil. Aqueous add solution (Rt). Render alkaline with 10-20 per cent NaOH and distil. ... [Pg.1296]

Plant samples (e.g. leaves, flowers, pollen) are first extracted into methanol or dilute aqueous sulfuric add. In the case of the methanol extracts, the solvent is evaporated and the residue re-extracted with dilute aqueous sulfuric acid. The aqueous add... [Pg.383]

Sulfur dioxide is by far the most important of the dioxides. It is a weak reductant in aqueous add but stronger in base where the sulfite ion (Section 12-13) is formed. [Pg.520]

Dissolve 3 g of the mixture in 30 mL of ether and transfer the mixture to a 125-mL separatory funnel using a little ether to complete the transfer. Add 10 mL of water and note which layer is organic and which is aqueous. Add 10 mL of a 10% aqueous solution of sodium bicarbonate to the funnel. Stopper the funnel and cautiously mix the contents. Vent the liberated carbon dioxide and then shake the mixture thoroughly with frequent venting of the funnel. Allow the layers to separate completely and then draw off the lower layer into a 50-mL Erlenmeyer flask (labeled Flask 1). What does this layer contain ... [Pg.108]

Which of the eight alcohols you identified in Problem 17.26 react with CrOj in aqueous add Show the products you would expect from each reaction. [Pg.719]

Called glycosides, carbohydrate acetals are named by first citing the alkyl group and replacing the -o e ending of the sugar with -aside. Like all acetals, glycosides are stable to neutral water. They aren t in equilibrium with an open-chain form, and they don t show mutarotation. They can, however, be converted back to the free monosaccharide by hydrolysis with aqueous add. [Pg.1065]

The most general method of preparation for tr amino adds is the ainido mslonatc synthesis, a straigbtforweird extension of the malonk ester syn thesis (Section 22.8). The reaction begins with conversion of diethyl Hcetamidomalonate into an enolate ion by treatment with base, followed tiy 3 2 alkylation with a primary alkyl halide. Hydrolysis of both the amide protectii group and the esters occurs when the alkylated product is warmed with aqueous add, and decarboxylation then takes place to yield an a-add. For example, aspartic add can be prepared irom ethyl bromoacetate ... [Pg.1104]

Aldehydes could also be attached to resin-bound serine or threonine through oxazolidine formation [81]. This linker has been used for the preparation of peptide aldehydes. The cleavage was performed with mild aqueous add at 60 °C. [Pg.59]


See other pages where Aqueous adds is mentioned: [Pg.1208]    [Pg.1208]    [Pg.1209]    [Pg.1210]    [Pg.1220]    [Pg.1222]    [Pg.1223]    [Pg.1229]    [Pg.1232]    [Pg.1238]    [Pg.1242]    [Pg.1245]    [Pg.1247]    [Pg.1255]    [Pg.1259]    [Pg.1260]    [Pg.1263]    [Pg.1271]    [Pg.1404]    [Pg.984]    [Pg.146]    [Pg.778]    [Pg.312]    [Pg.361]    [Pg.424]    [Pg.754]    [Pg.779]    [Pg.943]    [Pg.1043]    [Pg.400]    [Pg.120]   
See also in sourсe #XX -- [ Pg.159 ]




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