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Amides lead halides

Sn, Pb) and the synthetic methods for plumbylenes are restricted mainly to nncleophilic snbstitntion of divalent lead halides and amides with organolithium or Grignard... [Pg.2371]

C2BioHi2 derivatives with, e.g., R = ester, amine, amide, acyl halide, halogen, ether, alkyl, aryl, alkenyl or alkynyF , although a dialkyne will lead to some bis-carborane ... [Pg.180]

Palladium complexes also catalyze the carbonylation of halides. Aryl (see 13-13), vinylic, benzylic, and allylic halides (especially iodides) can be converted to carboxylic esters with CO, an alcohol or alkoxide, and a palladium complex. Similar reactivity was reported with vinyl triflates. Use of an amine instead of the alcohol or alkoxide leads to an amide. Reaction with an amine, AJBN, CO, and a tetraalkyltin catalyst also leads to an amide. Similar reaction with an alcohol, under Xe irradiation, leads to the ester. Benzylic and allylic halides were converted to carboxylic acids electrocatalytically, with CO and a cobalt imine complex. Vinylic halides were similarly converted with CO and nickel cyanide, under phase-transfer conditions. ... [Pg.565]

In an indirect amination process, acyl halides are converted to amino acids. Reaction of the acyl halide with a chiral oxazolidinone leads to a chiral amide, which reacts with the N=N unit of a dialkyl azodicarboxylate [R"02C—N=N—CO2R ]. Hydrolysis and catalytic hydrogenation leads to an amino acid with good enantioselectivity. ... [Pg.782]

A thio-substituted, quaternary ammonium salt can be synthesized by the Michael addition of an alkyl thiol to acrylamide in the presence of benzyl trimethyl ammonium hydroxide as a catalyst [793-795]. The reaction leads to the crystallization of the adducts in essentially quantitative yield. Reduction of the amides by lithium aluminum hydride in tetrahydrofuran solution produces the desired amines, which are converted to desired halide by reaction of the methyl iodide with the amines. The inhibitor is useful in controlling corrosion such as that caused by CO2 and H2S. [Pg.92]

Acyl-transfer reactions are some of the most important conversions in organic chemistry and biochemistry. Recent work has shown that adjacent cationic groups can also activate amides in acyl-transfer reactions. Friedel-Crafts acylations are known to proceed well with carboxylic acids, acid chlorides (and other halides), and acid anhydrides, but there are virtually no examples of acylations with simple amides.19 During studies related to unsaturated amides, we observed a cyclization reaction that is essentially an intramolecular acyl-transfer reaction involving an amide (eq 15). The indanone product is formed by a cyclization involving the dicationic species (40). To examine this further, the related amides 41 and 42 were studied in superacid promoted conversions (eqs 16-17). It was found that amide 42 leads to the indanone product while 41... [Pg.164]

O-Benzyllactaldehyde dimethylhydrazone 230 allows a substrate control in the addition reaction of organomagnesium halides, leading almost exclusively to the 5yn-isomer 231 (equation 155) . The resulting hydrazide can be reduced on Raney Ni to the corresponding iyw-aminoalcohol 232. The stereoselective Grignard addition to a similar A-formyl hydrazone 233 proceeds with 92% diastereoselectivity (equation 156). The silylation of the amide nitrogen by TMSCl provides the pure iyw-adduct . [Pg.574]

Kauffmann showed that treatment of halopyridines 34 with an excess of lithium dialkylamides at room temperature leads, via the intermediate 3,4-pyridyne (35), to an isomeric mixture of the amide addition products 36 and 37 (Scheme 11) [71AG(E)20]. Such reactions are inconsequential if they are performed at low temperatures where the rate of lithium halide elimination is slow. [Pg.194]

Reaction of the dilithiated species 416 and 419 with alkyl halides, aliphatic and aromatic aldehydes, and TMSC1 leads to products 421 and 422 in modest yields (Scheme 129) [83TL4735 86JCR(S)20]. In cases of the N-benzyl amides corresponding to 415 and 418, small amounts of benzylic functionalization is observed (see also later). The methyl and carbinol derivatives corresponding to 421 and 422 were quantitively hydrolyzed into useful synthons 423 and 424, and 425 and 426, respectively. [Pg.259]

Elimination-addition reactions of aryl halides with alkali-metal amides are discussed in Section 14-6C high-temperature copper-catalyzed amination, also effective, usually does not lead to rearrangement. [Pg.1611]


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See also in sourсe #XX -- [ Pg.4 , Pg.4 , Pg.5 , Pg.5 , Pg.7 ]




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