Cleavage of carbon–silicon bonds by lithium aluminium hydride in tetrahydrofuran

1968 ◽  
Vol 46 (15) ◽  
pp. 2507-2510 ◽  
Author(s):  
G. J. D. Peddle ◽  
D. N. Roark

It was shown that many silicon–carbon bonds were readily broken by lithium aluminium hydride in refluxing tetrahydrofuran. The rate of cleavage was dependent upon the nature of the leaving group and of the other groups present on the silicon. Carbon–tin bonds were cleaved more readily than carbon–silicon bonds while carbon–germanium bonds were not cleaved.

1984 ◽  
Vol 49 (4) ◽  
pp. 1009-1020 ◽  
Author(s):  
Irena Červená ◽  
Miroslav Protiva

Heating of 1-(2-iodobenzoyl)-4-methylpiperazine (II) with thiophenol and its 2-methyl, 4-methyl, 4-chloro and 2-hydroxymethyl derivatives in dimethylformamide in the presence of potassium carbonate, copper and cuprous iodide gave the piperazides IV-VIII; compound VIII was transformed by reduction with lithium aluminium hydride to the title compound I. The acid IX, obtained by a reaction of 5-chloro-2-iodobenzoic acid with 2-methylthiophenol, was reduced to the alcohol X, which was transformed via the chloride XI to 1-[5-chloro-2-(2-methylphenylthio)-benzyl]-4-methylpiperazine (XII), an open model of the neuroleptic agent clorothepin. Heating of 2,5-dichloroacetophenone with thiosalicylic acid afforded the keto acid XIII whose reaction with 1-methylpiperazine was carried out with the help of N,N"-carbonyldiimidazole. The piperazide XIV obtained was reduced on the one hand with sodium borohydride to the secondary alcohol XV, and with lithium aluminium hydride to 1-(2-[4-chloro-2-(1-hydroxyethyl)phenylthio]benzyl)-4-methylpiperazine (XVI) on the other. None of the dibasic piperazines (I, XII, XVI) did show antireserpine activity. In the general screening, some of the piperazides displayed a mild hypotensive (II, VIII, XIV, XV), adrenolytic (VIII), mild stimulating and antitussic (V), and spasmolytic, antiinflammatory and negatively ino- and chronotropic (XIV) activities.


1988 ◽  
Vol 43 (5) ◽  
pp. 571-573 ◽  
Author(s):  
Hubert Schmidbaur ◽  
Rudolf Hager

Abstract 1,1-Bis(trichlorosilyl)ethane, CH3CH(SiCl3)2 (1) is readily available through catalytic hydrosilylation of vinyltrichlorosilane and silicochloroform (90% yield), or through the base-induced reduction of acetyl chloride using again silicochloroform (60%). 1 can be converted into the title compound 2 in 80% yield by lithium aluminium hydride in di-n-butylether. Compound 2 is a highly volatile liquid (bp. 40-42 °C), not spontaneously inflamable in air. which is of interest as a precursor for chemical vapour deposition of hydrogen-containing silicon/carbon alloys (a-Si, C:H) and silicon carbide. Based on thermodynamical data, it is the least stable isomer of the composition C2Si2H10.


2017 ◽  
Vol 68 (1) ◽  
pp. 180-185
Author(s):  
Adriana Maria Andreica ◽  
Lucia Gansca ◽  
Irina Ciotlaus ◽  
Ioan Oprean

Were developed new and practical synthesis of (Z)-7-dodecene-1-yl acetate and (E)-9-dodecene-1-yl acetate. The routes involve, as the key step, the use of the mercury derivative of the terminal-alkyne w-functionalised as intermediate. The synthesis of (Z)-7-dodecene-1-yl acetate was based on a C6+C2=C8 and C8+C4=C12 coupling scheme, starting from 1,6-hexane-diol. The first coupling reaction took place between 1-tert-butoxy-6-bromo-hexane and lithium acetylide-ethylendiamine complex obtaining 1-tert-butoxy-oct-7-yne, which is transformed in di[tert-butoxy-oct-7-yne]mercury. The mercury derivative was directly lithiated and then alkylated with 1-bromobutane obtaining 1-tert-butoxy-dodec-7-yne. After acetylation and reduction with lithium aluminium hydride of 7-dodecyne-1-yl acetate gave (Z)-7-dodecene-1-yl acetate with 96 % purity. The synthesis of (E)-9-dodecene-1-yl acetate was based on a C8+C2=C10 and C10+C2=C12 coupling scheme, starting from 1,8-octane-diol. The first coupling reaction took place between 1-tert-butoxy-8-bromo-octane and lithium acetylide-ethylendiamine complex obtaining 1-tert-butoxy-dec-9-yne, which is transformed in di[tert-butoxy-dec-9-yne]mercury. The mercury derivative was directly lithiated and then alkylated with 1-bromoethane obtaining 1-tert-butoxy-dodec-9-yne. After reduction with lithium aluminium hydride of 1-tert-butoxy-(E)-9-dodecene and acetylation was obtained (E)-9-dodecene-1-yl acetate with 97 % purity.


1981 ◽  
Vol 46 (8) ◽  
pp. 1800-1807 ◽  
Author(s):  
Zdeněk Vejdělek ◽  
Marie Bartošová ◽  
Miroslav Protiva

4-Chloromethyl-s-hydrindacene (VIIa) was transformed via the malonic acid derivatives VIIIa and IXa to the acid Xb which afforded in four steps the homological acid Xc. Reactions of chlorides of both acids (XIbc ) with dimethylamine, 1-methylpiperazine and 1-(2-hydroxyethyl)piperazine led to the amides XIIbc-XIVbc which were reduced with lithium aluminium hydride to the title compounds IVcd-VIcd. The amines obtained show central neuroleptic effects only in subtoxic doses; they are also potent local anaesthetics and have significant spasmolytic activity of the neurotropic as well as musculotropic type.


1992 ◽  
Vol 57 (1) ◽  
pp. 194-203 ◽  
Author(s):  
Karel Šindelář ◽  
Vojtěch Kmoníček ◽  
Marta Hrubantová ◽  
Zdeněk Polívka

(Arylthio)benzoic acids IIa - IIe and VIb - VId were transformed via the acid chlorides to the N,N-dimethylamides which were reduced either with diborane "in situ" or with lithium aluminium hydride to N,N-dimethyl-(arylthio)benzylamines Ia - Ie and Vb - Vd. Leuckart reaction of the aldehydes IX and X with dimethylformamide and formic acid afforded directly the amines Va and Ve. Demethylation of the methoxy compounds Ia and Ve with hydrobromic acid resulted in the phenolic amines If and Vf. The most interesting N,N-dimethyl-4-(phenylthio)benzylamine (Va) hydrochloride showed affinity to cholinergic and 5-HT2 serotonin receptors in the rat brain and some properties considered indicative of antidepressant activity (inhibition of serotonin re-uptake in the brain and potentiation of yohimbine toxicity in mice).


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