Synthetic standards

These preparations, with those noted in the Preface to the Third Edition, cover a considerable proportion of the standard synthetic reactions. Most of these preparations come towards the end of Part II Preparations), and both elementary and advanced students should have no difficulty in selecting the preparative work they require. 

A standard synthetic sequence for building a six membered cyclic ketone onto an existing aromatic ring is shown in outline as follows Specify the reagents necessary for each step... 

A number of standard synthetic reference books are available. A review article by Kossell and Seliger discusses protective groups used in oligonucleotide syntheses, including protection for the phosphate group, which is not included in this book, and a series of articles describe various aspects of protective group chemistry. 

Synthesis of the title compound is representative of a number of syntheses of nonaromatic nitrogen heterocycles via Pd(Ill-catalyzed amination of olefins. These tosylated enamines are not readily available by standard synthetic methods, and show potential for further functionalization of the heterocycle. The saturated amine can be synthesized from the title compound by hydrogenation of the double bond followed by photolytic deprotection. ... 

In terms of cost, the effectiveness of the catalytic cycle in the ring closure makes this process economical in palladium. The first three steps in the reaction sequence -- ring opening of an epoxide by a Grignard reagent, converison of an alcohol to an amine with inversion, and sulfonamide formation from the amine — are all standard synthetic processes. 

Amidinate- and guanidinate-substituted boron halides are normally prepared using the two standard synthetic routes, i.e., salt-metathesis between suitable... 

Titanium(IV) guanidinato complexes, which are easily accessible by the standard synthetic routes (cf. Section III.B.2), have been studied as precursors to titanium carbonitride. Thin films of titanium carbonitride were obtained by low-pressure chemical vapor deposition of either [(Me3Si)2NC(NPE)2]TiCl(NMe2)2 or [Me2NC(NPE)2]2TiCl2 at 600 Most recent developments in this field... 

A set of chemicals that has been labeled or annotated for easy storage and retrieval and that is available for screening. Consists of compounds synthesized by combinatorial or standard synthetic methods, purchased from commercial or academic sources, or samples of natural products either as pure samples or as mixtures. 

A variety of standard synthetic methods have been used. Table I, which is not intended as an exhaustive compilation, lists some C3-C8 hydrocarbons which have been prepared (mainly in the last ten years or so) substituted with either l3C or 14C. Preparative details are given in the original literature. The route choice often depends on the available starting material. 

The selenols HSeC6H3-2,6-Mes2159 and HSeC6H3-2,6-Trip2155 can be synthesized in moderate yields by standard synthetic routes. They are made... 

Asymmetric allylic C-H activation of cydohexadiene systems has been used for the asymmetric synthesis of several compounds of pharmaceutical relevance. The key step in the asymmetric syntheses of the monoamine reuptake inhibitor (-i-)-indatrahne 185 was the C-H insertion reaction of the aryldiazoacetate 183 with 1,4-cyclohexadiene (Scheme 14.24). The product 184, obtained in 83% yield with 93% enantiomeric excess, is readily converted to (-i-)-indatraline using standard synthetic procedures [132]. 

Some non-standard synthetic pathways to compounds of the naph-tho[bc]pyran series are known. One consists in generation of the complex heterocyclic dehydrobenzene derivative 291, which then undergoes an intramolecular [4 + 2] cycloaddition to afford the bridge system 292. The latter is transformed into naphtho[bc]pyran-3-one 293 on reduction, followed by treatment with acid (8ITL4877 86AJC635). An unusual course... 

Set I. Standard Irradiated Sample Set II. Standard Synthetic Sample ... 

Catalytic reduction of chiral 2-(2-pyridyl)-l,3-oxazolidines and of 2-pyridyl imines, which are easily produced by standard synthetic means, followed by oxidation, results in the formation of chiral secondary amines as shown in equation 83333. The reaction occurs with a reasonable diastereoselectivity. 

The second well-documented research area that involved zero-valent nickel-catalyzed carboxylation was initiated by Dunach et al. during the 1990s [58a-c], These studies showed that electrochemically generated Ni(0)- and Mg(II)-based species represented good alternatives to the catalysts used in standard synthetic procedures. The formation of unsaturated carboxylic acids was proposed as a catalytic reaction initiated by Ni(0), although the exact mechanism and the obligatory... 

A case in point involves the electrochemical oxidation of vicinal diacids. A standard synthetic method for the preparation of carbon-carbon double bonds occurs by the bis-decarboxylation of such diacids. Even relatively strained, synthetically inaccessible double bonds have been introduced in this way, e.g., eqn 6. 

On treatment with sodium bis (2-methoxyethoxy)aluminium hydride (Scheme 16), 122 gave the aldehyde 123, which was converted by standard synthetic operations, into the methyl-O-benzylester 124. Acid hydrolysis of 124 followed by allylic epoxidation of the diol furnished the p-oxirane 125. On heating 125 in water containing sodium benzoate a remarkable chain of chemical events took place that resulted in the generation of (+)-pancratistatin (94) in 2% overall yield starting from bromobenzene. 

Buflavine [41]. 8-O-Demethylbuflavine, [41]. The ability of lithium tetramethylpiperidide to selectively deprotonate the methyl group of N,N-dimethylatylamides and the in situ capture of the resulting caibanion by a silyl chloride to form a,a-brs-silyl derivatives had been put to good use in a neat synthesis [42] of buflavine (147) and 8-O-demethylbuflavine (144) (Scheme 20). The a.a-disilylamide 148, thus secured from 149, was o-metallated and thence converted, by standard synthetic operations to the boronic acid 150. 

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