Halogenides, benzyl

HNS (7.5) can be prepared by many methods these include the reaction of nitro derivatives of toluene with benzaldehyde, the reaction of nitro derivatives of benzyl halogenides with alkaline agents by removing hydrogen halogenide, and the oxidation of nitro derivatives of toluene. 

Nucleophilic substitution of halogen in alkyl (benzyl) halogenides by ions, generated from 2-thiouracil, is leading to S- and O-derivatives of 2-thiouracil, which perspective as material... 

L-Phenylalanine has been produced continuously from ACA with the help of ACA acylase in an enzyme membrane reactor (EMR) with a space-time-yield of 277 g L 1 d1 83 . With ACL acylase, L-Ieucine was produced at 123-180 g L-1 d 1 in the same reactor set-up1821. The dehydroamino acid substrates can be prepared conveniently, either from 2-halogen carboxylic acid esters1841, or, specifically in the case of ACA, via the acetamidomalonic ester route by reaction with benzyl halogenides[851. 

The asymmetric arylation or alkylation of racemic secondary phosphines catalyzed by chiral Lewis acids in many cases led to the formation of enantiomerically enriched tertiary phosphines [120-129]. Chiral complexes of ruthenium, platinum, and palladium were used. For example, chiral complex Pt(Me-Duphos)(Ph)Br catalyzed asymmetric alkylation of secondary phosphines by various RCH2X (X=C1, Br, I) compounds with formation of tertiary phosphines (or their boranes) 200 in good yields and with 50-93% ee [121]. The enantioselective alkylation of secondary phosphines 201 with benzyl halogenides catalyzed by complexes [RuH (/-Pr-PHOX 203)2] led to the formation of tertiary phosphines 202 with 57-95% ee [123, 125]. Catalyst [(R)-Difluorophos 204)(dmpe]Ru(H)][BPh4] was effective at asymmetric alkylation of secmidaiy phosphines with benzyl bromides, whereas (R)-MeOBiPHEP 205/dmpe was more effective in the case of benzyl chlorides (Schemes 65, 66, and 67) [125—127]. 

Under phase transfer conditions (boiling benzene, 50% aquous sodium hydroxide solution and tetia-n-butylammonium hydrogenphosphate) benzamides are monoalkylated. In the solid-liquid PTC system potassium hydride, tetrahydrofuran and 18-crown-6, acidic trifluoroacetamides are rapidly deprotonated and alkylated with lower kyl, allyl and benzyl halogenides in high yield. Methylation of trifluoroacetamides is carried out under less basic conditions in KOH/acetone. A similar reaction in KOH/DMSO generally allows the efficient reaction of benzamide and acetanilide with primary alkyl halides with secondary halides only moderate yields are accomplished, whereas tertiary halogenides are not alkylated due to dehydrohalogenation. ... 

Patzold, E. Ohme, G. (1993) Water-soluble palladium(ll) phosphine complexes as catalysts in the hydrodehalogenation of allyl and benzyl halogenides under biphasic and phase-transfer conditions, J. Prakt. Chem. - Chem. Ztg., 335,181-4. 

Obtained (poor yield) by reaction of a benzyl halogenide with phloroacetophenone in the presence of sodium methoxide in methanol at r.t. (8%) [2878]. 

Treatment of 8-[(4-cyanophenyl)methoxy]-7-formyl-2-cyclopentyl-2,3,4,6,11,1 la-hexahydro-l//-pyrazino[l,2-i]isoquinoline-l,4-dione with (Et0)2P(0)CH2C00Et and NaH in THF at 40 °C overnight, or with (2-pyridylmethyl)-, 4-[(ethoxycarbonyl)benzyl]-, (4-nitrobenzyl)-, and (meth-oxymethyl)triphenylphosphonium halogenide in the presence of KH in THF at room temperature gave 7-ethylene derivatives 386 (98MIP7). 

Benzyl- und Allyl-halogenide werden durch Lithiumalanat/Chrom(III)-, Vanadium(III)-, Titan(III)- und Wolfram(VI)-chlorid-Systeme zu substituicrten Athanen, geminate Dihalogenide zu substituierten Athylenen gekoppelt, vicinale Dibromide zu Alkenen debromiert8. 

Wenn man ahnlich wie oben beschrieben verfahrt, jedoch anstelle von Trifluormethan-sulfonsaure-trimethylsilylester/Casiumfluorid ein reaktives Alkyl-halogenid (1-Jod-butan, Benzyl-bromid, Bromessigsaure-ethylester) verwendet, erhaltman substituierte 1-Alkyl-pyrrolidine1, z.B. l-Butyl-3,4-dimethoxycarbonyl-2-phenyl-pyrrolidin (82%), 1-Benzyl-3,4-dimethoxycarbonyl-2-phenyl-pyrrolidin (79%) oder 3,4-Dinlethoxycarbonyl-1-(ethoxy-carbonyl-methyl )-2-phenyl-pyrrolidin (74%). 

Die Reaktion von Formaldehyd-(O-benzyl-oxim) mit einem Alkyl-lithium bei tiefer Tem-peratur fiihrt zum N-Lithium-Derivat eines N-Alkyl-O-benzyl-hydroxylamins, das bei der Umsetzung mit einem weiteren Alkyl-lithium das N-Lithium-Derivat eines Dialkylamins ergibt dieses wird ohne Isolierung mit einem Alkyl-halogenid zu einem Trialkylamin al-kyliert1. 

The terminal carhanionic sites of "living" polymers can be reacted with various electrophilic compounds of yield (o)-functional polymers. Esters, nitriles, acid chlorides, anhydrides, lactones, epoxides, benzyl or allyl halogenides have been used for their high reactivity with metal organic sites, to yield appropriate functions.2 Carbon dioxide is also an efficient reagent to yield terminal carboxylic functions. 

At room temperature, formic acid (> 60%), fluorinated alcohols, m-cresol, phenol, and sulfuric acid (96%) act as solvents. At elevated temperatures, polyamide 6 and 66 are soluble in benzyl alcohol, glycols, and formamide. Concentrated formic acid and resorcinol are often used as adhesives for parts molded from polyamide because of their solvent effect. Alcoholic solutions of alkaline earth halogenides are of particular importance. For example, alcoholic calcium chloride solution has a pronounced solvent effect on semi-crystalline PA 6 and PA 66 grades. This property has to be considered for applications that expose polyamide to winter road conditions (e.g., liquid salts for deicing). Modification can significantly improve resistance. 

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