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Vicinal diamine

The next method Strike has for semi-direct amination is really weird, Strike is really exposing Strike s ignorance of chemistry with this dog. But if one looks hard at the articles cited, the potential is there. The authors came up with this little procedure that produced vicinal diamines out of alkenes [83]. Later they found that if they did a couple of things different, they would end up with a monoamine with the majority product being at the beta carbon. The following is a conjoining of the two paper s experimentals ... [Pg.186]

Syntheses and use of vicinal diamines with one or two N atoms included in heterocycle as chiral auxiliaries 98AG(E)2580. [Pg.222]

The conjugate addition of (R)- or fS -4-phenyl-2-oxa2oLidinone to nitroalkenes is catalyzed by r-BuOK at -78 C to give the addition product v/ith excellent diastereoselecdvity, the products are converted into vicinal diamines fEq 4 28 ... [Pg.78]

The asymmetric synthesis of unsymmetrical vicinal diamines by samarium diiodide induced reductive coupling of nitrones derived from aUphatic aldehydes with optically pure N-tert-butanesulfinyl aromatic imines has been recently reported [41]. For example, the reaction between nitrone 55 and... [Pg.14]

Reductive coupling of aldimines obtained from aromatic aldehydes and aromatic amines to generate vicinal diamines mediated by indium was carried out in aqueous ethanol (Eq. 11.59)." Small indium rods were used in this study. No side-product was observed due to unimolecular reduction. The presence of NH4CI was found to accelerate the reaction. The reaction fails completely in CH3CN, DMF, or wet DMF. The use of nonaromatic substrates also resulted in the failure of the reaction. [Pg.361]

The Michael addition of a nitrogen-centered nucleophile to nitroalkenes affords compounds that may serve as precursors of vicinal diamines, since the nitro group can be reduced to an amino function by reduction. The very convenient method for the preparation of 1,2-diamines is developed by the addition of C-ethylhydroxylamines to nitroalkenes followed by reduction with H2 in the presence of Pd/C (Eq. 4.24).30... [Pg.77]

Treatment of iV-(a-aminobenzyl)benzotriazoles 648 with samarium diiodide generates radicals 649 that undergo coupling to form vicinal diamines 650 (Scheme 101) <1992TL4763>. Formation of intermediate radicals 649 at low temperature is confirmed by EPR <19990L1755>. Short-living radicals 649 are readily converted to more stable radicals 651 by treatment with 2-methyl-2-nitrosopropane. [Pg.76]

Stereoselective hydride reduction of 1,2,5-thiadiazoline 1,1-dioxides 60 generates unsymmetrical 1,2,5-thiadiazol-idine 1,1-dioxides 61 <1998SL623> that can be readily converted to unsymmetrical vicinal diamines 62 with HBr in the presence of phenol (Scheme 5) <1996TL2859, 1998SL623>. The unsymmetrical thiadiazolidine 1,1-dioxides 63 can also be converted into 1,2-diketones 64 on treatment with selenium dioxide followed by alkaline hydrolysis (Equation 7) <1997SL671>. [Pg.531]

Solid-phase synthesis of dihydropteridinones has been achieved from 4,6-dichloro-5-nitropyrimidine <00TL8177>. A series of ethyl 7-aminopteridine-6-carboxylate derivatives has been prepared in one step from the reaction of vicinal diamines as 13-dialky 1-5,6-diamino-2-thiouracils with diethyl ( )-2,3-dicyanobutenedioate <99JHC1317>. The relative binding affinities to human dihydrofolate reductase of new 2,4-diaminopteridine derivatives... [Pg.308]

Using N-tert -butanesulfinilimines instead of carbonyl derivatives, constitutes an efficient synthetic route to optically pure asymmetric vicinal diamines that are widely used in asymmetric synthesis (Scheme 2.116) (536). [Pg.227]

A diastereoselective synthesis of vicinal diamines has been described79. The aldehydes 56 derived from chiral amino acids 55 were converted into the A-benzylimines 57 and the latter were treated with organometallic reagents R2M in the presence of cerium(III)... [Pg.547]

The A-trimethylsilylimines 68 (R = t-Bu, Ph, 2-MeCgH4 or 2-BrC6H4), which are prepared by the reaction of non-enolizable aldehydes with lithium bis(trimethylsilyl)amide, followed by trimethylsilyl chloride, undergo pinacolic coupling induced by NbCLt 2THF to yield the vicinal diamines 69 as mixtures of dl- and meso-isomers, in which the former predominate. Another method for the preparation of 1,2-diamines is by the combined action of the niobium tetrachloride/tetrahydrofuran complex and tributyltin hydride on cyanides RCN (R = /-Hu. Ph, cyclopentyl or pcnt-4-en-l-yl) (equation 32)82. [Pg.549]

In 2007, AntiUa and coworkers described the Brpnsted add-catalyzed desymmetrization of me yo-aziridines giving vicinal diamines [75]. hi recent years, chiral phosphoric acids have been widely recognized as powerful catalysts for the activation of imines. However, prior to this work, electrophiles other than imines or related substrates like enecarbamates or enamides have been omitted. In the presence of VAPOL-derived phosphoric acid catalyst (5)-16 (10 mol%) and azidotrimethylsilane as the nucleophile, aziridines 129 were converted into the corresponding ring-opened prodncts 130 in good yields and enantioselectivities (49-97%, 70-95% ee) (Scheme 53). [Pg.436]

Numerous HCLA have been developed and used for the enantioselective isomerization of oxiranes to allylic alcohols and, in most cases, their efficiency strongly depends on the structure of the oxirane. The HCLA species can be divided into two groups monohthiated vicinal diamines or ether-amines and dilithiated diamines or amido-alcoholates. [Pg.1179]

The absolute configuration of vicinal diamines can also be determined from the exciton Cotton effects of their bis[A7-(5-bromosalicylidene)]191 or bis[y-aminoenone] derivatives. Thus, both A -(5-bromosalicylidene) 1 and A -[4-(3-penten-2-one)] 2 derivatives of (7 )-l, 2-propanedi-amine show negative exciton Cotton effects, characteristic of the least congested rotamer I. [Pg.529]

Because vicinal diamines and 2-aminoalcohols are important components of natural products and medicinal agents, and used as ligands for metal-catalyzed reactions, especially in asymmetric synthesis, efficient methods for the compounds have been extensively investigated over the past decade. " ... [Pg.64]

Reductive coupling of aromatic aldimines leading to vicinal diamines proceeds with SmU, and is strongly accelerated by addition of a catalytic amount of or a stoichiometric amount of Yb(OTf)3. In the former... [Pg.65]

Treatment of an iV-(iV, A -dialkylaminoalkyl)benzotriazole, derived from an aldehyde and a secondary amine, with Sml2 affords a vicinal diamine via generation of the corresponding imine, one-electron reduction of the imine, and homocoupling (Equation (62)). ... [Pg.65]

Optically active chiral vicinal diamines are produced by Sml2-promoted reductive coupling of an imine derived from benzaldehyde and l-isopropyl-2-methoxyethylamine. Intermolecular coupling proceeds in a diastereoselective... [Pg.66]

Unsymmetrical vicinal diamines are prepared by reductive cross-coupling between nitrones and jY-/-butylsulfmyl imines with Sml2. The coupling proceeds in a high diastereoselective manner. Thus, optically pure unsymmetrical vicinal diamines are produced by using enantiomerically pure sulfinyl imines (Equation (74)). ... [Pg.68]

Nitrogen-transfer reactions of osmium imido species lead to cis diamines or amino alcohols. Reaction of 0s02(N-/-C4H9)2 [63174-13-0] with olefins produces vicinal diamines after reductive cleavage. Catalytic oxyamination of olefins using chloramine-T or AJ-chlor-AJ-argenocarbamates yields vicinal hydroxy toluenesulfonamides (112) or carbamates (113), respectively, which maybe deprotected to vicinal amino alcohols. [Pg.179]

Jung and Kohn have demonstrated the use of an external nitrogen nucleophile. Haloamination of al-kenes with NBS and cyanamide, followed by further manipulation, results in vicinal diamines in high yield (Scheme 68).134... [Pg.355]

By using glycine diphenylmethyl (Dpm) amide-derived Schiff base 22 as a key substrate and N-spiro chiral quaternary ammonium bromide lg as an ideal catalyst, a high enantioselectivity was achieved, even in the alkylation with less-reactive simple secondary alkyl halides, as shown in Table 5.5 [21]. This system offers a facile access to structurally diverse optically active vicinal diamines in combination with the subsequent reduction (Scheme 5.14) [21]. [Pg.85]

Stereoselective vicinal diamination of dihydropyridines 309 by electrophilic interaction with iodine in the presence of secondary amines leading to tetrahydropyrimidines 312 is described in [338, 339] (Scheme 3.107). The... [Pg.118]

Asaro, M. F. Nakayama, I. Wilson, R. B. Formation of sterically hindered primary vicinal diamines from vicinal and geminal dinitro compounds. /. Org. Chem. 1992, 57, 778-782. Rodriguez, H. Marquez, A. Chuaqui, C. A. Gomez, B. Oxidation of mesoionic oxazolones by oxygen. Tetrahedron 1991, 47, 5681-5688. Heras, M. Ventura, M. Linden, A. Villal-gordo, J. M. Reaction of a-iminomethylene amino esters with mono- and bidentate nucleophiles a straightforward route to 2-amino-lH-5-imidazolones. Tetrahedron 2001, 57, 4371—4388. [Pg.225]

A general strategy for the transformation of cyclic sulfates into vicinal diamines has been developed (Scheme 7) <1995TL9241>. This method has been extended to the synthesis of unsymmetrical diamines and various other amine derivatives by the controlled introduction of a second nucleophile into the reaction sequence <1995TL9241>. [Pg.168]

Reaction of 0s02(NR)2 with alkenes followed by reductive cleavage yields vicinal diamines (360) ... [Pg.313]

Finally, enantiomerically pure sulfinimines have also been used as precursors of chiral imidazolidines by 1,3-dipolar cycloaddition with azomethine ylids [181]. Reactions of different arylsulfinimines 245 with dipoles 246 are highly stereoselective, mainly affording diastereoisomer 247 (absolute configuration unequivocally established by X-ray studies), which was readily transformed into vicinal diamine 248 (Scheme 111). [Pg.115]


See other pages where Vicinal diamine is mentioned: [Pg.284]    [Pg.102]    [Pg.361]    [Pg.537]    [Pg.214]    [Pg.142]    [Pg.606]    [Pg.200]    [Pg.406]    [Pg.76]    [Pg.366]    [Pg.235]    [Pg.451]    [Pg.516]    [Pg.25]    [Pg.5]    [Pg.220]    [Pg.312]   
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See also in sourсe #XX -- [ Pg.311 ]




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E-Erythro vicinal diamine

Olefin vicinal diamines

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