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Acid chlorides reaction with lithium aluminum hydride

The hydroxyl equivalent weight of epoxy resins can be determined by several methods. The most common is esterification with acids, reaction with acetyl chloride, and reaction with lithium aluminum hydride. Infrared spectroscopy may also be used. [Pg.440]

An aiyl methane- or toluenesulfonate ester is stable to reduction with lithium aluminum hydride, to the acidic conditions used for nitration of an aromatic ring (HNO3/HOAC), and to the high temperatures (200-250°) of an Ullman reaction. Aiyl sulfonate esters, formed by reaction of a phenol with a sulfonyl chloride in pyridine or aqueous sodium hydroxide, are cleaved by warming in aqueous sodium hydroxide. ... [Pg.168]

A similar sequence starting with the acylation product (76) from metachlorophenylacetonitrile gives the halogenated tricyclic ketone 83. Condensation of that intermediate with ethyl bromoacetate in the presence of zinc (Reformatsky reaction) gives the hydroxyester 84. This product is then in turn dehydrated under acid conditions (85), saponified to the corresponding acid (86), and converted to the dimethyl-amide (87) by way of the acid chloride. The amide function is then reduced to the amine (88) with lithium aluminum hydride catalytic hydrogenation of the exocyclic double bond completes the synthesis of closiramine (89). This compound also exhibits antihistaminic activity. [Pg.424]

In the following year, this method was also applied to the total synthesis of tjipanazole FI (371) (784). For this synthesis, the required bisindole 1444 was obtained starting from 5-chloroindole (1440) in three steps and 47% overall yield. Acylation of 1440 with oxalyl chloride led to the glyoxylic acid chloride 1441. Transmetalation of indolylmagnesium bromide with zinc chloride, followed by addition of the acid chloride, provided the ot-diketone 1443. Exhaustive reduction of 1443 with lithium aluminum hydride (LiAlFl4) afforded the corresponding bisindolylethane 1444. Executing a similar reaction sequence as shown for the synthesis of tjipanazole F2 (372) (see Scheme 5.243), the chloroindoline (+ )-1445 was transformed to tjipanazole FI (371) in two steps and 50% overall yield (784) (Scheme 5.244). [Pg.359]

A carboxylic acid group may be introduced into the 2-position of dibenzofuran by Friedel-Crafts reaction with 2,2-dichloro-l,3-benzodioxole (catechol dichloromethylene ether) and hydrolysis of the resultant ester. Similarly, reaction with methylphenylcarbamoyl chloride produces the 2-(N-methyl-yV-phenylcarboxamide) or the 2,8-disubstituted derivative under more stringent conditions. Controlled reduction of these amides with lithium aluminum hydride supplies the corresponding aldehydes. ... [Pg.66]

Acylmetallocenes undergo many reactions shown by acylbenzenes (35, 87, 91, 116, 124), but a detailed discussion is not presented here. Reductions with either lithium aluminum hydride or sodium borohydride give the corresponding carbinols, while Clemmensen reduction, reduction with lithium aluminum hydride plus aluminum chloride, catalytic hydrogenation, etc., yield corresponding alkyl derivatives. Acetylferrocenes undergo a variety of base condensation reactions and can be oxidized to ferrocenecarboxylic acids without apparent oxidation of the iron atom. [Pg.66]

Hydroxjrmethylbenzof Jthiophenes are most conveniently prepared by reduction with lithium aluminum hydride of the corresponding carboxylic acid78,100 S37 485,486,521,528,540 or ester.77,87,336,337, 52i, 526 Lesg frequently, they are prepared by reduction of the corresponding aldehyde 100,487 or acid chloride,618 with sodium boro-hydride, or, in the case of 2-hydroxymethylbenzo[6]thiophenes, by reaction of the 2-lithium derivative with formaldehyde.90,628 3-Hydroxymethylbenzo[6]thiophene has been prepared from the corresponding aldehyde by means of a crossed Cannizzaro reaction... [Pg.312]

The structure XXII for rhynehophylline has been confirmed, and the relative stereochemistry at C-15 and C-20 has been elucidated, by a total synthesis (80) of (+) JV-methylrhynchophyllane (XXVI) (Marion s N-methylisorhynchophyllane), which had been prepared earlier by methyl-ation of (iso)rhynchophyllane with sodium methoxide and methyl iodide (28). The lactone (XXVII) of threo-3,4-diethyl-5-hydroxyvaleric acid was converted by reaction with phosphorus pentachloride into the corresponding S-chloroacid chloride (XXVIII), which on treatment with methylaniline gave the anilide XXIX. Reduction of XXIX with lithium aluminum hydride gave the aldehyde XXX, which slowly reacted with... [Pg.78]

The addition of nitrosyl chloride to cyclohexene in sulfur dioxide at low temperature21 -25, or the reaction of cyclohexene with 3-methylbutyl nitrite and hydrochloric acid (producing nitrosyl chloride in situ)25 gave only the tram-adduct 1, isolated in high yield as a crystalline nitroso dimer (azodioxy compound) with E configuration at the N—N double bond. The trans configuration of the chloro and nitroso groups (mixture of diaxial and diequatorial conform-ers) was deduced by IR and H-NMR analyses (a mixture of conformers with both axial and both equatorial substituents is apparent)23-25 and by reduction with lithium aluminum hydride in tetrahydrofuran to yield tram-2-chloro-l-cyclohexanamine (trans-2)23. [Pg.663]

Hydroxyketones are versatile intermediates in the synthesis of pharmaceutical intermediates and heterocyclic molecules. a-Aryl hydroxyketones have been prepared by reaction of aryl aldehydes with 1,4-dioxane followed by reduction with lithium aluminum hydride (LAH) and by the selective LAH reduction of a-silyloxy a,P-unsaturated esters." WissneC has shown that treatment of acid chlorides with tris(trimethylsilyloxy)ethylene affords alkyl and aryl hydroxymethyl ketones. 1-Hydroxy-3-phenyl-2-propanone (3) has been generated by the osmium-catalyzed oxidation of phenylpropene and by the palladium-catalyzed rearrangement of phenyl epoxy alcohoP both in 62% yield. [Pg.89]


See other pages where Acid chlorides reaction with lithium aluminum hydride is mentioned: [Pg.46]    [Pg.66]    [Pg.76]    [Pg.200]    [Pg.429]    [Pg.33]    [Pg.96]    [Pg.1295]    [Pg.1414]    [Pg.22]    [Pg.293]    [Pg.243]    [Pg.104]    [Pg.112]    [Pg.219]    [Pg.236]    [Pg.236]    [Pg.302]    [Pg.135]    [Pg.171]    [Pg.421]    [Pg.376]    [Pg.156]    [Pg.130]    [Pg.314]    [Pg.156]    [Pg.38]    [Pg.362]    [Pg.183]    [Pg.612]    [Pg.449]    [Pg.18]    [Pg.144]    [Pg.376]    [Pg.331]    [Pg.421]   
See also in sourсe #XX -- [ Pg.891 , Pg.922 ]




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Acid chlorides hydride

Acid chlorides, reactions

Acids Aluminum chloride

Aluminum chloride

Aluminum hydrides reactions with

Aluminum lithium with

Aluminum reaction with

Chloride reaction with acid

Hydride acidity

Hydride, lithium reaction with

Hydrides reaction with

Hydriding reaction

Lithium acids

Lithium aluminum hydride reaction

Lithium aluminum hydride reaction with

Lithium chloride, reaction

Reaction with lithium

Reactions hydrides

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