Olefinic amines, condensation with

Alkyl amines add photochemically to olefins a condensation occurs between the a-carbon atom of the amine and the terminal carbon atom of 1-olefins by what is probably a free-radical, chain reaction.291 Internally illumination of solutions, containing piperidine and octene-1, with a mercury discharge tube led to the formation of 2-n-oetylpiperidine (CXLV). 

TV-Alkylidenalkylamines were found in the reaction products of the transformation of 1-butylamine [147,148], cyclohexylamine and isopropylamine [149] on alumina, and were probably formed by the dehydrogenation of the primary amine to an imine, followed by its condensation with a second molecule of the amine [148], rather than by the dehydrogenation of the dialkylamine [147], The TV-alkylidenalkylamines R=N—R decompose to an olefin and an imine a cyclic process has been postulated [148] which explains the increases in reactivity of amines with secondary alkyls. Also butyronitrile has been detected in appreciable amounts in the reaction products of 1-butylamine on alumina at 500° C [147],... 

Cyclopropane compounds containing the olefin isostere replacement for the amide bond were prepared using Julia olefination chemistry. Aldehydes 39 and 40 were obtained by LAAIH4 reduction of the chiral w-butyl esters of 32 and 33, respectively, followed by swera oxidation of the corresponding alcohols (Figure 22). Condensation of the (S)-N-BOC-cyclohexylalanine sulfone 41 with aldehyde 39 gave after treatment with 2% Na(Hg) and deprotection, the trans and cis olefin-amines... 

The active methylene group of malonic acid readily takes part in condensations with aldehydes. The reaction is catalyzed by ammonia and various amines. Decarboxylation occurs at room temperature or upon heating to 100° to give, in most cases, a mixture of a,/3- and, y-olefinic... 

The reaction of aliphatic, alicyclic, and aromatic aldehydes and ketones with cyanoacetic ester, NCCHjCOjCjH, is general. The products are 0L,/3-olefinic cyanoacetates. The aldehydes are condensed with the ester in the presence of amines or with sodium cyanoacetate in the presence of sodium hydroxide, Similarly, cyanoacetic ester is condensed with ketones by catalysts such as acetamide or the acetates... 

For the preparation of the 10-ethyl-10-deaza analogues rac,L-(IV.108), cf,L-(IV.108), and /,l-(IV.108), a somewhat different scheme was followed to form the required racemic or optically active acid ester (IV.114) [124], The dilithium salt of 4- -propylbenzoic acid was condensed with allyl bromide, and the resulting acid was esterified with MeOH-HCl to obtain the olefinic ester, (IV.115). On oxidation with Ru02-NaI04, (IV.115) yielded (IV.114) (77%). Resolution of (IV.l 14) was achieved efficiently with J-(l-phenylethyl)amine. The remaining steps from (IV.l 14) to (IV. 108) were the same as those used to form the 10-methyl-10-deaza analogue, (IV.107). 

A variety of terminal functional groups and their chemical transformations on SAMs have been examined for example, (i) olefins—oxidation [23,24,131,132], hydroboration, and halogenation [23,24] (ii) amines—silyla-tion [145,146], coupling with carboxylic acids [22,146], and condensation with aldehydes [22,147] (iii) hydroxyl groups—reactions with anhydrides [148,149], isocyanates [150], epichlorohydrin [151], and chlorosilanes [152] (iv) carboxylic acids—formation of acyl chlorides [153], mixed anhydrides [154], and activated esters [148,155] (v) carboxylic esters—reduction and hydrolysis [156] (vi) thiols and sulfides—oxidation to generate disulfides [157-159] and sulfoxides [160] and (vii) aldehydes—condensation with active amines [161], Nucleophilic... 

Secondary and tertiary amines can be obtained if the hydroformylation of olefins is conducted in the presence of primary and secondary amines under elevated hydrogen partial pressures. Here the rhodium catalyst is involved in both steps, the hydroformylation of an olefin as well as the hydrogenation of the imine or enamine resulting from a condensation of the oxo-aldehyde with the amine (Scheme 14). This combination of hydroformylation and reductive amination is also known as hydroaminomethylation and has been applied to the synthesis of various substrates of pharmaceutical interest [55-57] as well as to the synthesis of macrocycles [60-63] and dendrimers [64,65]. 

Tropolone has been made from 1,2-cycloheptanedione by bromination and reduction, and by reaction with N-bromosuccinimide from cyclo-heptanone by bromination, hydrolysis, and reduction from diethyl pimelate by acyloin condensation and bromination from cyclo-heptatriene by permanganate oxidation from 3,5-dihydroxybenzoic acid by a multistep synthesis from 2,3-dimethoxybenzoic acid by a multistep synthesis from tropone by chlorination and hydrolysis, by amination with hydrazine and hydrolysis, or by photooxidation followed by reduction with thiourea from cyclopentadiene and tetra-fluoroethylene and from cyclopentadiene and dichloroketene. - The present procedure, based on the last method, is relatively simple and uses inexpensive starting materials. Step A exemplifies the 2 + 2 cycloaddition of dichloroketene to an olefin, " and the specific oycloadduot obtained has proved to be a useful intermediate in other syntheses. " Step B has been the subject of several mechanistic studies, " and its yield has been greatly improved by the isolation technique described above. This synthesis has also been extended to the preparation of various tropolone derivatives. - " ... 

Ir and nmr analysis of the condensation products of primary amines with aldehydes and ketones are in favor of the Schiff-base structure (46a). Nevertheless, these substances react with aryl azides in chloroform solution in the tautomeric enamine form (46b) yielding aminotriaiolines.206 225- 227 It proves that the dipolarophilic activity of an enamine olefin bond is much greater than that of an azomethine bond. 

Huisgen has stated that the driving force behind the 1,3-dipolar addition is stronger the more the loss of T-bond energy in the reactants is overcompensated by the energy of the two new bond energy is O-N < N-N < C-N, azides do not add at all to aldehydes and ketones and add with more difficulty to nitriles than to olefins. Phenyl azide, for instance, adds preferentially to the C-C double bond of acrylonitrile.194 103 This is also the reason why the condensation products of aldehydes and primary amines, which essentially exist in the Schiff-base structure 46a, react in the tautomeric enamine form 46b.2 ... 

The Reaction of 2 with Amines or Amides. Two hundred mg of 2 was placed, under nitrogen, in a double Schlenk tube fitted with a reflux condenser and septum adapter. The amine or amide (5 ml) was added, and the mixture was placed in an oil bath preheated to 200°C. After the mixture turned black it was heated for an additional 20 min, cooled, and passed through the filter disc. This solution can be used directly for hydrogenation, or ether can be added to produce a Mack precipitate. The ether washed precipitate can also be used in olefin hydrogenations. 

Notable examples of general synthetic procedures in Volume 47 include the synthesis of aromatic aldehydes (from dichloro-methyl methyl ether), aliphatic aldehydes (from alkyl halides and trimethylamine oxide and by oxidation of alcohols using dimethyl sulfoxide, dicyclohexylcarbodiimide, and pyridinum trifluoro-acetate the latter method is particularly useful since the conditions are so mild), carbethoxycycloalkanones (from sodium hydride, diethyl carbonate, and the cycloalkanone), m-dialkylbenzenes (from the />-isomer by isomerization with hydrogen fluoride and boron trifluoride), and the deamination of amines (by conversion to the nitrosoamide and thermolysis to the ester). Other general methods are represented by the synthesis of 1,1-difluoro olefins (from sodium chlorodifluoroacetate, triphenyl phosphine, and an aldehyde or ketone), the nitration of aromatic rings (with ni-tronium tetrafluoroborate), the reductive methylation of aromatic nitro compounds (with formaldehyde and hydrogen), the synthesis of dialkyl ketones (from carboxylic acids and iron powder), and the preparation of 1-substituted cyclopropanols (from the condensation of a l,3-dichloro-2-propanol derivative and ethyl-... 

A recent paper by Kiselyov et al. (91) reported the synthesis of two small SP discrete libraries of tetrahydroquinolines LI and L2 inspired by a three-component condensation reaction in solution (92-94) as depicted in Eig. 6.8. The scope of this condensation had been expanded by other groups (95-97), and the use of polymer-supjxMted metal catalysts had also been reported (98, 99) however, an SP route with a broad tolerance for different amines, aldehydes, and olefins had still not been defined prior to this work. 

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