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Carboxamides reaction with

Chlorosulfonyl isocyanate has been used to introduce 3-carboxamide groups. The initial product, an A -chlorosulfonylcarboxamide, is treated with tri-n-butylstannanc to form the primary carboxamide[15], 3-Cyano groups can also be introduced using chlorosulfonyl isocyanate. The intermediate N-chlorosulfonylindole-3-carboxamide is converted to 3-cyanoindole on reaction with triethylamine[16] or DMF[17],... [Pg.113]

It is proposed that the boric acid reacts with the carboxylic acid to form a mixed anhydride as the actual acylating agent.913 Upon reaction with an amine, this intermediate forms the desired carboxamide and regenerates the catalytically active boric acid. [Pg.138]

The addition of Grignard reagents to aldehydes, ketones, and esters is the basis for the synthesis of a wide variety of alcohols, and several examples are given in Scheme 7.3. Primary alcohols can be made from formaldehyde (Entry 1) or, with addition of two carbons, from ethylene oxide (Entry 2). Secondary alcohols are obtained from aldehydes (Entries 3 to 6) or formate esters (Entry 7). Tertiary alcohols can be made from esters (Entries 8 and 9) or ketones (Entry 10). Lactones give diols (Entry 11). Aldehydes can be prepared from trialkyl orthoformate esters (Entries 12 and 13). Ketones can be made from nitriles (Entries 14 and 15), pyridine-2-thiol esters (Entry 16), N-methoxy-A-methyl carboxamides (Entries 17 and 18), or anhydrides (Entry 19). Carboxylic acids are available by reaction with C02 (Entries 20 to 22). Amines can be prepared from imines (Entry 23). Two-step procedures that involve formation and dehydration of alcohols provide routes to certain alkenes (Entries 24 and 25). [Pg.638]

Carbamates by Reaction with Carbamoylazoles (Azole-iV-Carboxamides) of Secondary Amines... [Pg.144]

Chiral dirhodium(II) catalysts with carboxylate or carboxamidate ligands have recently been developed to take advantage of their versatility in metal carbene transformation, and these have now become the catalysts of choice for cyclopropanation. Chiral carboxylate ligands 195,103 196,104 and 197105 have been used for tetrasubstitution around a dirhodium(II) core. However, the enantioselectivity in intermolecular reactions with simple ketenes is marginal. [Pg.316]

The reaction of Bi2HnNH22 with chlorides of carboxylic acids proceeds not to carboxamides, as would have been expected, but to carboximido acids. Reaction of the amine takes place only when deprotonated with strong base. The high p KR value of the ammonium group makes reactions with CH-acidic compounds difficult, as the latter might be stronger acids than the Bi2HiiNH3. ... [Pg.117]

The catalysed two-phase alkylation of carboxamides has the advantages of speed and simplicity over the traditional procedures and provides a valuable route to secondary and tertiary amines by hydrolysis or reduction of the amides, respectively. The procedure appears to be limited, however, to reactions with primary haloalkanes and dialkyl sulphates, as secondary haloalkanes are totally unreactive [6, 7]. The use of iodoalkanes should be avoided, on account of the inhibiting effect of the released iodide ion on the catalyst. Also, the A-alkylation reaction is generally susceptible to steric effects, as seen by the low yields in the A -cthylation of (V-/-butylacetamide and of A-ethylpivalamide [6]. However, the low steric demand of the formyl group permits A,A-dialkylation and it is possible to obtain, after hydrolysis in 60% ethanolic sulphuric acid, the secondary amines having one (or, in some cases, two) bulky substituent(s) [7]. [Pg.175]

Before turning to specific results we will have a look at the properties of rhodium(II) acetates/carboxamidates as catalysts for reactions with diazocompounds as the substrates via carbenoid intermediates. Rhodium(II) has a d7 electron configuration, forming the lantern type dimers with bridging carboxylates. The single electrons in the respective dz2 orbitals form an electron... [Pg.364]

Displacement of nitrogen from diazonium salts derived from 4- or 5-aminotriazoles can be achieved in the same manner as for other aromatic diazonium salts for example, diazotization of 4-amino-triazole-5-carboxamide and reaction with iodine and potassium iodide gives the 4-iodo derivative. ... [Pg.71]

The parent cis- and tra s-octahydroquinazolin-4(l//)-ones 261 were synthesized by Armarego [71JCS(C)238] by the reaction of the cis- and trans-2-amino-l-carboxamides 260 with aqueous formaldehyde. The yields were only moderate. [Pg.389]

Scheme 15.8 Diastereocontrol in C-H insertion reactions with chiral dirhodium(II) carboxamidate catalysts. Scheme 15.8 Diastereocontrol in C-H insertion reactions with chiral dirhodium(II) carboxamidate catalysts.
Interesting reagents for such MCRs from the viewpoint of selectivity tuning are 5-aminopyrazoles containing carboxamide substituent. In the first article concerning the behavior of these aminozoles in the reactions with cyclic 1,3-diketone and aldehydes, it was found that only one direction of the treatment leads to tricyclic Biginelli-like heterocycles 61 (Scheme 30) [96]. [Pg.61]

Carbamazepine Carbamazepine, 5H-dibenz[b,f]azepine-5-carboxamide (9.5.2), is synthesized by reacting 5H-dibenz[b,f]azepine and phosgene, which forms 5-chlorcarboxy-5H-dibenz-[b,f]azepine (9.5.1), and its subsequent reaction with ammonia to give the... [Pg.129]


See other pages where Carboxamides reaction with is mentioned: [Pg.40]    [Pg.40]    [Pg.314]    [Pg.82]    [Pg.42]    [Pg.289]    [Pg.176]    [Pg.148]    [Pg.153]    [Pg.133]    [Pg.669]    [Pg.300]    [Pg.186]    [Pg.112]    [Pg.441]    [Pg.1024]    [Pg.128]    [Pg.511]    [Pg.345]    [Pg.264]    [Pg.534]    [Pg.173]   


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2- Aminothiophene-3-carboxamide, reaction with

Carboxamidates

Carboxamidation

Carboxamides

Carboxamides reaction with electrophiles

With carboxamides

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