Amide reaction summary

The reaction conditions of example 1 were repeated using a different hydrocarbyl aluminum activator in a 4 1 molar ratio to chromium(III) tris(bis(trimethylsilyl)-amide). Reactions were conducted at an ethylene pressure of 100 psi at 70°C for 60 minutes. Neither 1-butene nor 1-decene was detected in the product mixture. A summary of reaction scooping is provided in Table 1. 

A brief summary of important amide reactions follows reduction... 

In summary, the first lesson learned was the ability of CO2 released during the activation of a carboxylic acid to catalyze the subsequent amidation reaction. Although the mechanistic aspects need some clarification, the utility of this phenomenon in organic synthesis, especially on large scale, is clear. 

On the basis of the reactions presented in this chapter, write reaction summary charts for esters and amides similar to the chart for acyl halides (Figure 20-1). Compare the number of reactions for each of the compound classes. Is this information consistent with your understanding of the relative reactivity of each of the functional groups ... 

Formation of the excited amide anion of coelenteramide as the light emitter in the luminescence reaction of coelenterazine was experimentally supported by the experiment of Hori et al. (1973a), in which 2-methyl analogue of coelenterazine was used as the model compound. The summary of their work is as follows In the presence of oxygen, la and lb in DMF emitted bright blue luminescence (Amax 480 and 470 nm, respectively), and produced the reaction products Ha and lib, respectively. The fluorescence emission of lib (Amax 470 nm) and that of the spent chemiluminescence reaction of lb, both in DMF plus a base (potassium r-butoxide), were identical to the chemiluminescence emission of lb in DMF. The fluorescence emission of Ha... 

Those polyester FBAs containing a benzoxazole group are usually prepared from the appropriate o-aminophenol and carboxylic acid (11.45 Y = OH) or one of its derivatives, as shown in Scheme 11.10. The reaction proceeds via an intermediate amide and it can be advantageous to start from an acid derivative such as the acid chloride (11.45 Y = Cl) or ester (11.45 Y = OEt), which are both more effective acylating agents. The preparation of compound 11.36, shown in Scheme 11.11, illustrates this process, but the optimum conditions for ring closure vary considerably from one structure to another. The article by Gold contains a valuable and detailed summary [4]. 

In summary, (R)-phenylglycine amide 1 is an excellent chiral auxiliary in the asymmetric Strecker reaction with pivaldehyde or 3,4-dimethoxyphenylacetone. Nearly diastereomerically pure amino nitriles can be obtained via a crystallization-induced asymmetric transformation in water or water/methanol. This practical one-pot asymmetric Strecker synthesis of (R,S)-3 in water leads to the straightforward synthesis of (S)-tert-leucine 7. Because (S)-phenylglycine amide is also available, this can be used if the other enantiomer of a target molecule is required. More examples are currently under investigation to extend the scope of this procedure. ... 

To present the take-home message of the current work Present-active In summary, (R)-phenylglycine amide 1 is an excellent chiral auxiliary in the asymmetric Strecker reaction with pivaldehyde or 3,4-dimethoxyphenyl-acetone. (From Boesten et al.. 2001)... 

In summary, the direct insertion of zinc dust to organic halides is an excellent method for preparing a broad range of polyfunctional organozinc halides bearing various functional groups like an ester" , an ether, an acetate" , a ketone, cyano", halide" , N,N-bis(trimethylsilyl)amino °, primary and secondary amino, amide, phthalimide , sulfide, sulfoxide and sulfone , boronic ester , enone " or a phosphonate . An alternative method is based on transmetalation reactions. 

In summary, it may be stated that the reaction of acyl esters of aldoses and aldobioses (see Section III, p. 92) with ammonia consists of a set of competitive pathways, including intramolecular O —> N migrations of acyl groups, deacylations, and transesterifications, with formation of aldose amides and variable proportions of the free sugar as the principal products. Significant proportions of basic or insoluble polymeric substances were not observed with aldose acetates or benzoates, although occurrence of extensive browning indicates the probable formation of soluble melanoidins. 

The modification of carboxyl groups has been carried out (1) by esterification with dry methanol and HC1, (2) by esterification with aliphatic diazo compounds, (3) by the formation of adducts with carbodi-imides, or (4) by the formation of amides through activation with carbodiimides. Both complete and, apparently specific, partial modification of the 11 free carboxyl groups have been obtained. In general, the first method suffers from the denaturing medium, the second from incomplete reaction, and the third from the uncertain nature of the products. The fourth procedure is perhaps subject to the least question. There are a total of 11 free carboxyl groups in native RNase-A l (Val), 5/ (Asp), 5y(Glu). A summary of the derivatives is given in Table V. 

Several blue tetra- and octanuclear Pt complexes, prepared upon reaction of cis-[Pt(NH3)2(H20)2]2+ with open and cyclic amides, as well as cyclic imides and a uracil nu-cleobase, and comprised of binuclear building blocks interacting through Pt-Pt bond formation, have been isolated and structurally characterized in recent years. Without exception, the average Pt oxidation state in these compounds is 2.25. Nevertheless, the structure and mode of action as antitumor agents of the Platinum Pyrimidine Blues , as prepared by Rosenberg in the early 70 s, remain elusive. This account represents a summary of our present knowledge on cationic Platinum Blues , with a focus on those blues obtained from cis-[Pt(NH3)2(H20)2]2+ and pyrimidine nucleobases, and presents speculations on reasonable alternative structures. 

Amines can be prepared by reduction of nitro compounds, nitriles, and amides. Because the details of these reactions have been discussed previously, they are presented here in summary form only. 

Summary Treatment of geminal silyldiamines with monohalo silanes leads to the formation of 1-amino-1,3-disilazanes. Mono-NH-SiF-functional cyclodisilazanes can be isolated by ring closure of their lithium derivatives in the reaction with trifluorosilanes. Lithium salts of these cyclodisilazanes react with H-acidic compounds like alcohols as amides and with unsaturated compounds like aldehydes as silaimines. 

Tablet Summary of ring closing reactions of the amino blocked cystine f)is(methyl-amides)...

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