Benzyl amine synthesis

Entry Substrates Temperature (°C) Catalyst Product /time (h) 

Aliphatic sulfonimines also reacted smoothly, but the stereoselectivity with 19a was poor. Variation of the pincer complex catalyst did not change the stereoselectivity (cf. entries 6 and 7). The reaction did not proceed while using commonly used (non-pincer) catalysts [43]. 

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ANILINES, BENZYL AMINES, AND ANALOGUES An orally active local anesthetic agent that can be used as an (intiarrhythmic agent is meobenti ne (57). Its patented synthesis starts with -hydroxyphenyl nitrile and proceeds by dimethyl sulfate etherification and Raney nickel reduction to Alkylation of -methyl-dimethylthiourea with completes l.he synthesis of meobenti ne (57). ... 

Several recent articles describe the ring-opening of chiral epoxides under microwave irradiation conditions (see also Scheme 6.103). In the context of the preparation of novel /32-adrenoceptor agonists related to formoterol and salmeterol, Fairhurst and a team from Novartis have described the synthesis of chiral ethanolamines by solvent-free microwave-assisted ring-opening of a suitable chiral epoxide precursor with secondary benzylated amines (Scheme 6.129) [262]. At 110 °C, the reaction occurred... 

An early example of this strategy is the palladium black catalyzed conversion of (Z)-2-buten-l,4-diol with primary amines (cyclohexyl amine, 2-aminoethanol, -hexyl amine, aniline) at 120 °C to give A-substituted pyrroles in 46-93% yield [119]. Trost extended this animation to the synthesis of a series of AT-benzyl amines 169 from the readily available a-acetoxy-a-vinylketones 168 [120]. This methodology allowed for the facile preparation of pyrrolo-fused steroids. 

An efficient primary amine synthesis via iV-diisobutylaluminium imines has been described. A cyanide R CN (R1 = Bu, CsHn, Ph, 2-furyl or 2-thienyl) is treated with diisobutylaluminium hydride and the product is converted into the amine by reaction with an organomagnesium or organolithium compound R2M (R2 = Bu, t-Bu, allyl or benzyl)... 

Enzyme-based processes for the resolution of chiral amines have been widely reported [2, 3] and are used in the manufacture of pharmaceuticals, for example, BASF s process for chiral benzylic amine intermediates. Scheme 13.1 [4]. The methods used are enantioselective hydrolysis of an amide and enantioselective synthesis of an amide, both of which are kinetic resolutions. For high optical purity products the processes depend upon a large difference in the catalyzed reaction rates of each enantiomer. 

Alkylation of aziridines amine synthesis.3 N-Substituted aziridines (alkyl, benzyl, silyl, Boc) react with lithium dialkylcuprates in the presence of BF3 etherate (excess) with opening of the ring to give primary or secondary amines. 

Asymmetric synthesis of amino aeUs. Optically active amino acids can be prepared by addition of hydrogen cyanide to SchifT bases prepared from aliphatic aldehydes (representing the R group) and optically active benzylic amines (representing the... 

Fontaine and coworkers have recently reported the synthesis of a supported aza-lactone via atom radical transfer polymerization (ATRP) [9]. This method involved the preparation of a Wang resin-supported initiator, followed by subsequent ATR polymerization between 2-vinyl-4,4-dimethyl-5-oxazolone (VAZ) and styrene to generate several macroporous, aza-lactone functionalized resins with different architectures. These were shown to scavenge benzyl amines in a highly efficient fashion (Scheme 8.5). 

Application of this methodology led to the synthesis of indolizidine and quinolizidine alkaloids. Condensation of 228 with benzyl amine followed by aza-annulation produced dihydropyridone 229 (Scheme 16).59-74 Stereoselective hydrogenation in the presence of Na2CC>3... 

Chapter 7 benzyl as a protecting group in amine synthesis ... 

The Sommelet reaction, also known as the Sommelet oxidation, is the oxidation of benzyl halides (1) to the corresponding aldehydes (3) using hexamethylenetetramine (HMTA) followed by hydrolysis of the hexaminium salt 2.1-3 This reaction is closely related to the Delepine amine synthesis, the Duff aldehyde synthesis, and the Krtihnke reaction (see Section 7.10.3). 

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