Amines Organic Syntheses procedures

The synthesis of 4-phenyhnorpholme by Cu-catalyzed amination of diphenylzinc with A-benzoyloxymorpholine 2a has been also presented as an Organic Synthesis procedure . 

Amide and electron-poor aniline nucleophiles have also been employed in heteroaryl halide amination reactions. For example, an organic synthesis procedure was recently reported for the synthesis of ethyl 4-[(6-chloropyridin-3-yl)amino] benzoate via Ai-arylation of ethyl 4-aminobenzoate with 2-chloro-4-iodopyridine (Eq. 32) [220]. Beletskaya has illustrated that bromoindole derivatives can be coupled with amides utilizing either Xantphos or 3,5-(Cp3)2Xantphos (22) as the ligand in good yield (Eq. 33) [169]. 

The procedure described is essentially that of Shioiri and Yamada. Diphenyl phosphorazidate is a useful and versatile reagent in organic synthesis. It has been used for racemlzatlon-free peptide syntheses, thiol ester synthesis, a modified Curtius reaction, an esterification of a-substituted carboxylic acld, formation of diketoplperazines, alkyl azide synthesis, phosphorylation of alcohols and amines,and polymerization of amino acids and peptides. - Furthermore, diphenyl phosphorazidate acts as a nitrene source and as a 1,3-dipole.An example in the ring contraction of cyclic ketones to form cycloalkanecarboxylic acids is presented in the next procedure, this volume. 

A number of synthetic procedures are available (Ai2). (2) For precisely defined stoichiometries, the isobaric, two-bulb method of Herold is preferred H5, H6, H2). (2) To generate compounds suitable for organic synthesis work, graphite and alkali metal may be directly combined, and heated under inert gas (Pl, lA). (5) Electrolysis of fused melts has been reported to be effective iN2). 4) Although alkali metal -amine solutions will react with graphite, solvent molecules co-inter-calate with the alkali metal. Utilization of alkali metal-aromatic radical anion solutions suffers the same problem. 

Two complementary procedures have been developed for alkylation of secondary amines [11] - both of which involve the use an excess of amine to drive the reaction to completion. The remaining amine was removed from the required tertiary amine using a polymer supported isocyanate 5 as a nucleophilic scavenger (under thermodynamic control) (Table 1 entry 2). The use of this amine scavenger has subsequently been applied in the purification of urea-based libraries prepared by solid-phase organic synthesis [12],... 

We have synthesized VPI-5 with a variety of organic agents such as amines and quaternary ammonium cations. The synthesis procedure depends upon the type of organic agent and we will illustrate an "amine" synthesis with DPA and a "quat." synthesis with TBA. Table I lists reproducible procedures. We have provided an example of a "small" scale synthesis (DPA) and a fairly "large" scale synthesis (TBA) to show that these procedures can be scaled-up. Below we discuss the essential details of these two procedures. VPI-5 that has been crystallized with the use of DPA and TBA will be denoted DPA-VPI-5 and TBA-VPI-5, respectively. 

Many of the simple mono- and polyamines are commercially available, but designer specific ligands require the use of conventional organic synthetic techniques. Methods of amine complex synthesis are usually central-metal specific, but summaries of procedures used for Cr n8,9 are... 

Reactions on alumina surfaces. The water present in commerciaUy available aluminas is known to effect some undesired side reactions and has been used to some extent to effect desired transformations ie.g., selective hydrolysis, 2, 3601). Posner et ah reasoned that replacement of the water in alumina by alcohols, thiols, or amines should result in doped-aluminas useful for organic synthesis. In the general procedure the alumina is dehydrated by heating at 400° and 0.06 torr for 24 hr. and is then stirred with the dope in an inert solvent. 

---