Amines aminoalcohols, synthesi

As a result of interaction of 843 and pyridine, the adduct 845 is formed [53], The structures of coordination compounds 844 and 845 were proved by x-ray diffraction. As shown above (Sec. 3.4.3.2), the direct ammonia synthesis [55,56] with participation of various ligands (especially aliphatic, aromatic, and heterocyclic amines, aminoalcohols), elemental metals (or their oxides), and NH4SCN in mostly non-aqueous media, opens definite possibilities for obtaining thiocyanate complexes. In this respect, transformation (4.9) should be mentioned [57] ... 

Table 6.1. Variation of the aldehydes in the 1,3-aminoalcohol synthesis by using 2-phenylethyl-amine as constant building block...

Rao et al. [100] for the first time report the biomimetic approach for the synthesis of a single enantiomer of p-aminoalcohol. In this approach p-cyclodextrin formed by the inclusion of complex 77 with racemic aryloxyepoxide which reacted enantioselectively with amines imder solid state condition to give the product in 100% ee and 70-79% isolated yield. The yield which was above 50% was explained in terms of continuous racemization of the... 

Y. Yamamoto and co-workers used L-aspartic acid 4-methyl ester (108) as their starting material for the synthesis of preussin [64]. The ester was transformed in nine steps to the TBDPS-protected aminoalcohol 109 (Scheme 28). Allylation of the iST-Boc-protected amine using allyl bromide... 

Enantiomerically pure aminoalcohols, which are readily available by reduction of a-amino acids, can be converted into alkoxycarbonylating reagents suitable for the solid-phase synthesis of oligocarbamates (Figure 16.26). Particularly convenient alkoxycarbonylating reagents are 4-nitrophenyl carbonates, which can be prepared from alcohols and 4-nitrophenyl chloroformate, and which react smoothly with aliphatic primary or secondary amines to yield the corresponding carbamates. 

The traditional synthesis of cyclic sulfimidates from /3-aminoalcohols and SOCl2 in the presence of amine as a base has been developed further to the preparation of the enantiopure monocyclic as well fused sulfimidates (Schemes 26 and 27). 1,2,3-Oxathiazolidine mono-.Y-oxides are readily oxidized to corresponding sulfamidates by RuCR and NalCb, and the synthesis of sulfamidates can be performed in a one-pot procedure from -aminoalcohols without isolation of intermediate sulfimidates (Equation 37). The reaction of sulfamate esters 145 with PhI(OAc)2 and various catalysts proved to be a reliable method for the enantioselective preparation of cyclic sulfamidates 146 (Equation 35). 

Pteridine synthesis from pyrazine precursors are usually applied in such cases where the formation of special derivatives cannot be achieved easily by the pyrimidine approach. Methyl 3-amino-2-pyrazinecarboxylate (362) reacts with thiophosgene to give the corresponding 3-isothiocyanato derivative (363) which cyclizes with primary amines, arylalkylamines, aminoalcohols, amino acids,... 

Intramolecular nucleophilic displacement of an activated alcohol by amines using -aminoalcohols constitutes a very powerful method for the synthesis of azetidines . Particularly useful is the cyclization of... 

Epoxides may be cleaved by amines. This reaction is used in the synthesis of aminoalcohols (53) studied as potential adrenergic drugs (Scheme 21). The amine cleavage of the epoxide and the subsequent nitrous acid deamination of the aminoalcohol are used for the ring enlargement of alicyclic ketones (TiffeneauDemjanov reaction). By this sequence of reactions, for example, cycloheptanone (54) may be converted to cydooctanone (55) (Scheme 21). 

A simple and efficient method for the small-scale combinatorial synthesis of polyamine derivatives from diverse aminoalcohols and amines has been proposed by Renault and co-workers.33... 

This chapter focuses on the metal-catalyzed amination of alcohols and related compounds such as aminoalcohols, phenols and di- and polyhydroxy compounds. Details of the synthesis of amines with acidic catalysts, including zeolites, mixed oxides and metal phosphates, can be found elsewhere [3,5-7]. 

A new process for synthesis of 3-aminomethyl-3,5,5-trimethylcyclohexylamine (IPDA) has been investigated. The reaction was performed in two steps. In the first step bis (3-cyano-3,5,5 trimethylcyclohexylidene) azine (IPNA) was synthesized from 3-cyano-3,5,5 trimethyl- 1 oxo cyclohexane (IPN) and hydrazine hydrate in solvent. The reaction yield was nearly quantitative. In the second step the azine (IPNA) was hydrogenated under mild conditions on a Raney nickel or cobalt catalyst in the presence of a small amount of ammonia. Isophorone diamine (IPDA) was obtained at high yields (90-95 %). But the main interest of a such process is to minimize the production of byproducts (aminoalcohol, azabicyclic compound, secondary amine) and to use less severe pressure conditions than those generally employed. 

Aminoalcohols (87), important intermediates in the synthesis of x-ray contrast media, can be prepared either by reaction of 4,7-dihydro-1,3-dioxepins with chlorine in acetonitrile and treatment of the A -acyl derivative (85) with Na2COj and 50% NaOH <83USP4389526> (cf. also <920PP536 or by ring opening of epoxides (88) with NH3, amines or azides <81EUP33426> (Scheme 13). For the phenylselenofluoration of 4,7-dihydro-l,3-dioxepins <90TL663>. 

Alkylation of aryl derivatives Synthesis of amines from 2-aminoalcohols... 

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