Alcohols, acetylation benzoyl derivatives

Liquid amines can be further purified via their acetyl or benzoyl derivatives (vide supra). Solid amines can be recrystallised from water, alcohol, toluene or toluene-petroleum ether. Care should be taken in handling large quantities of amines because their vapours are harmful (possibly carcinogenic) and they are readily absorbed through the skin. 

Ammodendrine, C jH oONj, HjO (No. 1, table, p. 116). The base has m.p. 73 °, becomes anhydrous at 70-80°, and then melts at 50-60°, Wd i 0°. The salts are amorphous and deliquescent except the hydriodide B. HI, which forms a crystalline precipitate, m.p. 218-20°, from alcohol, and the perchlorate, m.p. 199-200°. An amorphous A-benzoyl derivative was obtained. With methyl iodide ammodendrine behaves as a secondary base, yielding first A-methylammodendrine hydriodide (a crystalline precipitate, m.p. 183-5°, from a mixture of alcohol and acetone), and at the second stage iV-methylammodendrine methiodide, m.p. 163-5°. On hydrogenation ammodendrine furnishes a dihydro-base, which is hydrolysed into acetic acid and 2 3 -dipiperidyl, C oHjoNj, and must be dZ-A-acetyl-3-a-piperidylpiperidine. Ammodendrine should therefore be acetyltetrahydroanabasine and is of biological interest as the first recorded occurrence of this type of alkaloid in the Leguminoss. ... 

Aryl substituents at N2 tend to stabilize the 1-bromide center, and a range of poly-O-acetyl-a-D-glycosyl bromides with iV-benzoyl,112 N-tosyl,163-171 N-(2,4-dinitrophenyl),16S and other N-substituents168 have been prepared, all of which yield glycosides on treatment with alcohols. The N-benzoyl derivative (LXI) readily undergoes an intramolecular rearrangement112- 113 to give the oxazoline derivative hydrobromide (LXII), from which the free base (LXIII) can be prepared.113... 

The equilibrium between the open and closed form of the aldehyde-amide formed from acylated derivatives of A pyrrolines (conkurchine series6) has been studied for the N-benzoyl (6) and the iV-acetyl (7) compounds.7 It appears that for the benzoyl derivative (6) the equilibrium is such that the open form is favoured, whereas for the acetyl derivative (7) the cyclic form predominates [there is an absence of C=0 aldehydic vibrations in the i.r. of (7)]. However, in both cases, reduction with sodium borohydride gave the two corresponding alcohol amides. 

From aliphatic 2-nitroalkanols, readily accessible via the Henry reaction,i3i the reduction by aluminum amalgam also gives hydroxylamines as intermediates, further reduced to amino alcohols.i mildly basic conditions permit the acylation of the amino group, and the amino alcohols can be conveniently isolated as the N-acetyl or benzoyl derivatives. 

Synthesis ofLysergic Acid, By reacting N-benzoyl-3-(B-carboxyethyl)-dihydroindole (see JCS, 3158 (1931) for the preparation of this compound) with thionyl chloride, followed by aluminum chloride gives l-benzoyl-5-keto-l,2,2a,3,4,5-hexahydrobenzindole. This is then brominated to give the 4-bromo-derivative, which is converted to the ketol-ketone by reacting with methylamine acetone ethylene ketol. This is then hydrolized by acid to yield the diketone and treated with sodium methoxide to convert it to the tetracyclic ketone. Acetylate and reduce this ketone with sodium borohydride to get the alcohol, which is converted to the hydrochloride form, as usual. 

The uniquely distinguished axial alcohol at C5 was activated by triflation and the resultant triflate was displaced by the action of tetra n-butylammonium azide in benzene at room temperature. Compound 25 was thus available in 86% yield from alcohol 24. Hydrogenolysis ((H24 d(OH)2C) followed by acetylation afforded compound 26 in 96% yield. TTie richly detailed NMR spectrum (490 MHz) of 26 was identical in every respect with that of the L-antipode derived from reaction of NeuSAc, first with acidic methanol and then with benzoyl chloride under the influence of DMAP. The infrared and mass spectra, as well as the chromatographic characteristics of the two materials, were identical. 

Acylphosphonates, e.g. (5), possess highly reactive carbonyl groups and—somewhat like trilialomethyl ketones—exhibit both ketone and carboxy character, forming oximes and adducts, and also carboxylate derivatives via C—P bond cleavage.7 Their hemiacetal derivatives have been studied by 31P-NMR in the presence of alcohols, for the representative acetyl and benzoyl compounds (5 R = Me, Ph). Equilibrium and... 

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