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Hydroxyl groups, tertiary

Poly(amido amine)s carrying additional functions as side substituents can be easily obtained, starting with the appropriate monomers 38,44>. In fact, hydroxyl groups, tertiary amino groups, allyl groups, etc., if present in the monomers, do not interfere with the polymerization process. [Pg.63]

The type of alcohol produced depends on the carbonyl compound Substituents present on the carbonyl group of an aldehyde or ketone stay there—they become sub stituents on the carbon that bears the hydroxyl group m the product Thus as shown m Table 14 3 (following page) formaldehyde reacts with Grignard reagents to yield pri mary alcohols aldehydes yield secondary alcohols and ketones yield tertiary alcohols... [Pg.595]

In keeping with its biogenetic origin m three molecules of acetic acid mevalonic acid has six carbon atoms The conversion of mevalonate to isopentenyl pyrophosphate involves loss of the extra carbon as carbon dioxide First the alcohol hydroxyl groups of mevalonate are converted to phosphate ester functions—they are enzymatically phosphorylated with introduction of a simple phosphate at the tertiary site and a pyrophosphate at the primary site Decarboxylation m concert with loss of the terti ary phosphate introduces a carbon-carbon double bond and gives isopentenyl pyrophos phate the fundamental building block for formation of isoprenoid natural products... [Pg.1091]

Methylbutynol. 2-Methyl-3-butyn-2-ol [115-19-5] prepared by ethynylation of acetone, is the simplest of the tertiary ethynols, and serves as a prototype to illustrate their versatile reactions. There are three reactive sites, ie, hydroxyl group, triple bond, and acetylenic hydrogen. Although the triple bonds and acetylenic hydrogens behave similarly in methylbutynol and in propargyl alcohol, the reactivity of the hydroxyl groups is very different. [Pg.112]

Ammonia, and Amines. Isopropanolamine is the product of propylene oxide and ammonia ia the presence of water (see Alkanolamines). Propylene oxide reacts with isopropanolamine or other primary or secondary amines to produce A/- and A/,A/-disubstituted isopropanolamines. Propylene oxide further reacts with the hydroxyl group of the alkanolamines to form polyether polyol derivatives of tertiary amines (50), or of secondary amines ia the presence of a strong base catalyst (51). [Pg.135]

Perbenzoic acid gave a doubly unsaturated triol monobenzoate. Only two hydroxyl groups could be acetylated, and one was tertiary. The saturated triol reacted with lead tetracetate to give an a glycol. When reacted with chromic acid, it gave a hydroxy lactone. From these observations, Windaus and Gmndmann (11) described the correct stmcture for ergosterol (1). [Pg.125]

Compounds with amino or hydroxyl groups decrease in biodegradabihty relative to degree of saturation, in the following order primary, secondary, then tertiary carbon atom of attachment. [Pg.166]

Amino Alcohols. Reaction of chloroformate is much more rapid at the amino group than at the hydroxyl group (4—8). Thus the hydroxy carbamates, which can be cyclized with base to yield 2-oxazoHdones, can be selectively prepared (29). Nonionic detergents may be prepared from poly[(ethylene glycol) bis(chloroformates)] and long-chain tertiary amino alcohols (30). [Pg.39]

TtM use of vinyl chloroformate tor N-dealkytatlon of tertiary amines, protection of amino groups, protection of hydroxyl groups or formation of Z-ketoimidazoles. Synthesis of vtnyl cartxjnates by means of fluoro or chiorofonnates. [Pg.279]

This compound is also described as diethanol-p-toluidine in the older literature. Anilines bearing hydroxyl groups are preferred because they are less volatile than anilines without polar substituents. Tertiary aromatic amines with para-halogen substitution have also been reported for use in adhesives [42]. [Pg.833]

Up to 1915 it had been established that oscine was a tertiary bas containing one hydroxyl group, and that the second oxygen atom wi probably present in an etheric linkage. It was also known that on oxid ... [Pg.86]

The three alkaloids concerned, morphine, codeine and thebaine, all behave as tertiary bases. Morphine contains two hydroxyl groups of which one is phenolic and the other a secondary alcohol group. On methylation of the phenolic hydroxyl codeine results. On oxidation, codeine is transformed into codeinone by conversion of the secondary alcohol group into a carbonyl group, and when thebaine is boiled with A-sulphuric acid for a few minutes, it is hydrolysed into codeinone and methyl sulphate, and in other ways thebaine has been shown to contain two methoxyl groups. That the relationship between the three alkaloids is close may be illustrated by the following slightly extended formula —... [Pg.222]

Heliotrine, CigH2,05N, m.p. 125-6°, [ajn — 75° (CHCI3), yields a methiodide, m.p. 108-111°, and contains one methoxyl group, two hydroxyl groups and a tertiary nitrogen atom. On alkaline hydrolysis it forms heliotridine (p. 607) and heliotric acid (p. 613). In presence of platinic oxide it absorbs two molecules of hydrogen and affords, as scission products, heliotric acid and hydroxyheliotridane (p. 607). [Pg.603]

Many aromatic steroids submitted to the Birch reduction contain hydroxyl groups which are deprotonated to the corresponding alkoxides during the reduction, particularly if a tertiary alcohol is used as the proton donoi. The steroidal alkoxides and the one derived from the proton donor often precipitate and cause foaming of the reaction mixture, as was noted by Wilds and Nelson. These alkoxides can be kept in solution by adding an excess of the proton donor alcohol to the mixture the alcohol also assists in dissolving the starting hydroxylic steroid. A particularly useful reaction medium for hydroxylic steroids contains ammonia, tetrahydrofuran and -butyl alcohol in the volume ratio of 2 1 (Procedure 2, section V). This mixture... [Pg.26]

The reactivity of various steroid alcohols decreases in the order primary > secondary (equatorial) > secondary (axial) > tertiary. The only systematic investigation relating to the selective protection of steroidal hydroxyl functions has been carried out with the cathylate (ethyl carbonate) group. Since only equatorial hydroxyl groups form cathylates this ester has been used as a diagnostic tool to elucidate the configuration of secondary alcohols. [Pg.380]

The tertiary 17) -hydroxyl group does not form bulky enol ethers and mixed acetals. However, tetrahydropyranyl ethers are obtained from 17a-ethynyl-17]3-hydroxy compounds. Tetrahydropyranyl ethers have also been prepared from tertiary 17a-hydroxyl groups. ... [Pg.404]

In Sarett s total synthesis of cortisone, mild acid conditions were developed for the hydration of an ethoxyacetylenic carbinol to the ester without complete dehydration of the tertiary hydroxyl group. An acid-sensitive ketal group in another part of the molecule was also maintained. [Pg.181]


See other pages where Hydroxyl groups, tertiary is mentioned: [Pg.18]    [Pg.404]    [Pg.135]    [Pg.164]    [Pg.267]    [Pg.76]    [Pg.73]    [Pg.60]    [Pg.30]    [Pg.220]    [Pg.223]    [Pg.238]    [Pg.245]    [Pg.279]    [Pg.325]    [Pg.389]    [Pg.389]    [Pg.416]    [Pg.565]    [Pg.586]    [Pg.606]    [Pg.670]    [Pg.708]    [Pg.711]    [Pg.734]    [Pg.736]    [Pg.750]    [Pg.42]    [Pg.226]    [Pg.238]    [Pg.426]    [Pg.225]   


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Tertiary hydroxyls

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