Highly reactive, liquid diacrylamides via synergistic combination of spatially arranged curing moieties

• Maximilian Maier,
• Magnus S. Schmidt,
• Markus Ringwald and
• Christoph P. Fik

Beilstein J. Org. Chem. 2017, 13, 372–383, doi:10.3762/bjoc.13.40

• Havis et al. through the dropwise addition of 7 in chloroform to a solution of primary amines such as aminocyclohexane at room temperature [30]. After stirring for 24 hours the resulting diamino hydrobromide was isolated in moderate yield. To avoid quenching/scavenging of the hydrobromide in the later

A chemoselective and continuous synthesis of m-sulfamoylbenzamide analogues

• Arno Verlee,
• Thomas Heugebaert,
• Tom van der Meer,
• Pavel I. Kerchev,
• Frank Van Breusegem and
• Christian V. Stevens

Beilstein J. Org. Chem. 2017, 13, 303–312, doi:10.3762/bjoc.13.33

• used for a range of m-sulfamoylbenzamide analogues (vide infra). However, if the first reagent (F2) is a secondary amine, the chemoselectivity decreases substantially when the current process is used. Secondary amines are more nucleophilic as compared to primary amines, resulting in a higher percentage

• chemoselectivity was measured by LC–MS and is presented in Table 4. The chemoselectivity varied between 50 and 99%. Apart from the reactions involving 3-fluoroaniline, the chemoselectivity was above 70% for primary amines and above 60% for secondary amines. The side products which are being formed are the double

• account but, the screening of these analogues should already give a good indication which compounds are of interest. Medium throughput synthesis if F2 are primary amines Between each sample a washing step with CH3CN was included to eliminate any side reaction of undesired amines in the system. For the

Highly bulky and stable geometry-constrained iminopyridines: Synthesis, structure and application in Pd-catalyzed Suzuki coupling of aryl chlorides

• Yi Lai,
• Zhijian Zong,
• Yujie Tang,
• Weimin Mo,
• Nan Sun,
• Baoxiang Hu,
• Zhenlu Shen,
• Liqun Jin,
• Wen-hua Sun and
• Xinquan Hu

Beilstein J. Org. Chem. 2017, 13, 213–221, doi:10.3762/bjoc.13.24

• comprise symmetrical frameworks, such as bipyridine [44][45][46], biimidazole [47][48], and diimine [49][50][51][52][53]. Moreover iminopyridines were attractive for a more straightforward preparation, the condensation of pyridine-2-carboxaldehyde or ketone and the relevant primary amines. By this work a

The synthesis of α-aryl-α-aminophosphonates and α-aryl-α-aminophosphine oxides by the microwave-assisted Pudovik reaction

• Erika Bálint,
• Ádám Tajti,
• Anna Ádám,
• István Csontos,
• Konstantin Karaghiosoff,
• Mátyás Czugler,
• Péter Ábrányi-Balogh and
• György Keglevich

Beilstein J. Org. Chem. 2017, 13, 76–86, doi:10.3762/bjoc.13.10

• and α-aryl-α-aminophosphine oxides was synthesized by the microwave-assisted solvent-free addition of dialkyl phosphites and diphenylphosphine oxide, respectively, to imines formed from benzaldehyde derivatives and primary amines. After optimization, the reactivity was mapped, and the fine mechanism

• preparation of new derivatives. Results and Discussion Synthesis of α-aryl-α-aminophosphonates and α-aminophosphine oxides At first, the imine starting materials 1 were prepared by the condensation of benzaldehyde and its chloro-substituted derivatives with primary amines, such as butyl-, cyclohexylamine or

Continuous-flow synthesis of primary amines: Metal-free reduction of aliphatic and aromatic nitro derivatives with trichlorosilane

• Riccardo Porta,
• Alessandra Puglisi,
• Giacomo Colombo,
• Sergio Rossi and
• Maurizio Benaglia

Beilstein J. Org. Chem. 2016, 12, 2614–2619, doi:10.3762/bjoc.12.257

• performed for the first time under continuous-flow conditions. Aromatic as well as aliphatic nitro derivatives were converted to the corresponding primary amines in high yields and very short reaction times with no need for purification. The methodology was also extended to the synthesis of two

Construction of bis-, tris- and tetrahydrazones by addition of azoalkenes to amines and ammonia

• Artem N. Semakin,
• Aleksandr O. Kokuev,
• Yulia V. Nelyubina,
• Alexey Yu. Sukhorukov,
• Petr A. Zhmurov,
• Sema L. Ioffe and
• Vladimir A. Tartakovsky

Beilstein J. Org. Chem. 2016, 12, 2471–2477, doi:10.3762/bjoc.12.241

• our knowledge, there is only one report on the formation of bishydrazones as undesirable products in reactions of some primary amines with N-tosylhydrazone of o-bromophenacyl bromide [50]. We suppose that extension of the scope of azoalkene–amine coupling to ammonia, primary amines and polyamines

Methylenelactide: vinyl polymerization and spatial reactivity effects

• Judita Britner and
• Helmut Ritter

Beilstein J. Org. Chem. 2016, 12, 2378–2389, doi:10.3762/bjoc.12.232

• quantitative amidation reactions with aliphatic primary amines under mild conditions [7]. In the underlying study, we focused on spatial effects with respect to interactions between neighboring lactide rings. Based on these findings, polymer analogous reactions of poly(MLA) with different alcohols were

Stereo- and regioselectivity of the hetero-Diels–Alder reaction of nitroso derivatives with conjugated dienes

• Lucie Brulíková,
• Aidan Harrison,
• Marvin J. Miller and
• Jan Hlaváč

Beilstein J. Org. Chem. 2016, 12, 1949–1980, doi:10.3762/bjoc.12.184

• ) [36]. The introduction of the nitroso group through the transformation of pendant functional groups includes the oxidation of primary amines [37][38][39][40][41] (Scheme 4) and hydroxamic acids [42][43][44] (Scheme 5) and the reduction of nitro compounds [45][46][47]. As oxidants for the amino group

Microwave-assisted synthesis of (aminomethylene)bisphosphine oxides and (aminomethylene)bisphosphonates by a three-component condensation

• Erika Bálint,
• Ádám Tajti,
• Anna Dzielak,
• Gerhard Hägele and
• György Keglevich

Beilstein J. Org. Chem. 2016, 12, 1493–1502, doi:10.3762/bjoc.12.146

• Chemistry, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany 10.3762/bjoc.12.146 Abstract A practical method was elaborated for the synthesis of (aminomethylene)bisphosphine oxides comprising the catalyst- and solvent-free microwave-assisted three-component condensation of primary amines

• oxide, and we aimed at the preparation of new derivatives. Results and Discussion Synthesis of alkylamino- and (phenylaminomethylene)bisphosphine oxides In the first series of experiments, the condensation of primary amines, such as butyl-, cyclohexyl- and benzylamine or aniline with triethyl

• primary amines with triethyl orthoformate and diethyl phosphite. Spectral characterization of N-ethyl- (4) and N-formyl- (5) (aminomethylene)bisphosphonates and imine-type intermediates 6a and 6b. Synthesis of (dialkylaminomethylene)bisphosphonates 8a–g. Condensation of aniline, triethyl orthoformate and

A cross-metathesis approach to novel pantothenamide derivatives

• Jinming Guan,
• Matthew Hachey,
• Lekha Puri,
• Vanessa Howieson,
• Kevin J. Saliba and
• Karine Auclair

Beilstein J. Org. Chem. 2016, 12, 963–968, doi:10.3762/bjoc.12.95

• (10b), propylacrylamide (10c), and pentylacrylamide (10d, Table 1). Based on the classification reported by Grubbs [20], these substrates are type II when used in the presence of catalyst 3. Propyl- and pentylacrylamide (10c and 10d) were synthesized from acrylic acid and the respective primary amines

Synthesis of 2,1-benzisoxazole-3(1H)-ones by base-mediated photochemical N–O bond-forming cyclization of 2-azidobenzoic acids

• Daria Yu. Dzhons and
• Andrei V. Budruev

Beilstein J. Org. Chem. 2016, 12, 874–881, doi:10.3762/bjoc.12.86

• another report [39], the major products formed from triplet nitrenes are primary amines 4 through hydrogen-atom abstraction [58], secondary amines, 1,2-arylhydrazides and azo compounds 5, which are obtained by recombination of radicals [59]. Moreover, it was shown that yields of primary amines increased

• ethanol. As can be seen in Table 3, the photolysis of 1c,d in a 1,4-dioxane/water mixture under these conditions lead to decreased yields of 2c,d and to the formation of azepine 3c and primary amines 4c,d with significant yields. An explanation for the decreased yields observed for isoxazoles 2c,d may be

• the photo-induced breaking of the C–Br bond that completely changed the way of the reaction. However, this possibility does not explain the formation of primary amines 4c,d. It should be noted that the photolysis of double ortho-substituted azides (Table 3, entries 2, 4, R2 ≠ H) did not lead to the

Muraymycin nucleoside-peptide antibiotics: uridine-derived natural products as lead structures for the development of novel antibacterial agents

• Daniel Wiegmann,
• Stefan Koppermann,
• Marius Wirth,
• Giuliana Niro,
• Kristin Leyerer and
• Christian Ducho

Beilstein J. Org. Chem. 2016, 12, 769–795, doi:10.3762/bjoc.12.77

• separated by column chromatography. After debenzylation, the resultant primary amines were connected with amido aldehydes 6 substituted with different moieties R and R' by reductive amination with R being either a hydroxy group or a hydrogen and R' representing an alkyl, allyl, ester or a protected amino

Synthesis of bi- and bis-1,2,3-triazoles by copper-catalyzed Huisgen cycloaddition: A family of valuable products by click chemistry

• Zhan-Jiang Zheng,
• Ding Wang,
• Zheng Xu and
• Li-Wen Xu

Beilstein J. Org. Chem. 2015, 11, 2557–2576, doi:10.3762/bjoc.11.276

• was reacted with different azides catalyzed by the Cu(II)–TBTA complex and sodium ascorbate in a bi-phasic system of CH2Cl2/H2O as the solvent, giving the desired bistriazoles 59 in good yield; (3) Deprotection of the N-Boc group with TFA, and the obtained primary amines was transformed to the

Beyond catalyst deactivation: cross-metathesis involving olefins containing N-heteroaromatics

• Kevin Lafaye,
• Cyril Bosset,
• Lionel Nicolas,
• Amandine Guérinot and
• Janine Cossy

Beilstein J. Org. Chem. 2015, 11, 2223–2241, doi:10.3762/bjoc.11.241

• , several pathways are involved in the amine-induced catalyst decomposition depending on the nature of the amine and of the ruthenium complex. Non-bulky primary amines can attack directly benzylidene species and are responsible for the fast degradation of the catalyst. In the case of a phosphine-containing

Preparative semiconductor photoredox catalysis: An emerging theme in organic synthesis

• David W. Manley and
• John C. Walton

Beilstein J. Org. Chem. 2015, 11, 1570–1582, doi:10.3762/bjoc.11.173

• 1,2-diazine or imine co-reactants to yield functionalized hydrazones or benzylanilines. SCPC with tertiary amines enabled electron-deficient alkenes to be alkylated and furoquinolinones to be accessed. Primary amines on their own led to self-reactions involving C–N coupling and, with terminal diamines

• product 11a was formed by attack of this species anti to the menthyloxy substituent of 6. The electrophilic intermediate radical thus formed readily ring closed on to the electron rich aromatic ring furnishing 11a and 11b after oxidative rearomatization. When primary amines 12 were irradiated on their own

Radical-mediated dehydrative preparation of cyclic imides using (NH₄)₂S₂O₈–DMSO: application to the synthesis of vernakalant

• Dnyaneshwar N. Garad,
• Subhash D. Tanpure and
• Santosh B. Mhaske

Beilstein J. Org. Chem. 2015, 11, 1008–1016, doi:10.3762/bjoc.11.113

• convenient one-pot process for the synthesis of miscellaneous cyclic imides in high yields starting from readily available primary amines and cyclic anhydrides. A plausible radical mechanism involving DMSO has been proposed. The application of this facile one-pot imide forming process has been demonstrated

• method to construct the imide functionality is to react the corresponding primary amines with cyclic anhydrides to form amic acids, which are then cyclized using acetic anhydride and sodium acetate in a separate step [26]. Hexamethyldisilazane–zinc chloride has also become one of the most widely used

• a convenient one-pot process for the preparation of structurally diverse cyclic imides starting from readily available primary amines and cyclic anhydrides using APS–DMSO as an efficient and novel dehydrating reagent and its application to a drug synthesis. The scope of the developed protocol was

Multivalent dendritic polyglycerolamine with arginine and histidine end groups for efficient siRNA transfection

• Fatemeh Sheikhi Mehrabadi,
• Hanxiang Zeng,
• Mark Johnson,
• Cathleen Schlesener,
• Zhibin Guan and
• Rainer Haag

Beilstein J. Org. Chem. 2015, 11, 763–772, doi:10.3762/bjoc.11.86

• -2025, USA 10.3762/bjoc.11.86 Abstract The success of siRNA-based therapeutics highly depends on a safe and efficient delivery of siRNA into the cytosol. In this study, we post-modified the primary amines on dendritic polyglycerolamine (dPG-NH2) with different ratios of two relevant amino acids, namely

• broader distribution of the final nanoparticles. The size of dPG-13Arg and dPG-13His complexes was slightly smaller than the other dPG-based vectors. The surface charge of the final nanoparticles was comparable to the corresponding complexes of siRNA and dPG-NH2 50% with terminal primary amines and about

• cytotoxicity of the nanoplexes. Replacing the primary amines on dPG-NH2 with histidine groups would possibly decrease the density of positive charge on dPG and increase cell viability. The best cytotoxicity profile was observed for dPG-8Arg30His with no considerable cytotoxicity (cell viability ≥ 90%) up to N

Exploring monovalent and multivalent peptides for the inhibition of FBP21-tWW

• Lisa Maria Henning,
• Sumati Bhatia,
• Miriam Bertazzon,
• Michaela Marczynke,
• Oliver Seitz,
• Rudolf Volkmer,
• Rainer Haag and
• Christian Freund

Beilstein J. Org. Chem. 2015, 11, 701–706, doi:10.3762/bjoc.11.80

• literature [19]. The transformation started from the mesylation of the hydroxy groups on the hPG. In the next step, the mesylated polyglycerol was converted to poly(glycerol azide). In the last step, azide functionalities (N3) were reduced to primary amines (-NH2) via Staudinger reduction to obtain the

Stereoselective cathodic synthesis of 8-substituted (1R,3R,4S)-menthylamines

• Carolin Edinger,
• Jörn Kulisch and
• Siegfried R. Waldvogel

Beilstein J. Org. Chem. 2015, 11, 294–301, doi:10.3762/bjoc.11.34

• [19] are used as precursors for chiral β-amino alcohols. As precursors for α-chiral primary amines, fenchone [20] and camphor [21][22] are typically employed. Furthermore, optically pure dehydroabietylamine is readily available and applicable without further modification [23][24][25]. Among the

Lewis acid-catalyzed redox-neutral amination of 2-(3-pyrroline-1-yl)benzaldehydes via intramolecular [1,5]-hydride shift/isomerization reaction

• Chun-Huan Jiang,
• Xiantao Lei,
• Le Zhen,
• Hong-Jin Du,
• Xiaoan Wen,
• Qing-Long Xu and
• Hongbin Sun

Beilstein J. Org. Chem. 2014, 10, 2892–2896, doi:10.3762/bjoc.10.306

• , 3u, and 3v in good yields (76–88% yields), respectively. Finally, primary amines were examined. The reaction with excess benzylamine (5.0 equiv) in the presence of Zn(OTf)2 as the catalyst afforded the desired product 3w in 98% yield. However, when n-BuNH2 was used as the substrate, the yield was

Synthesis of nanodiamond derivatives carrying amino functions and quantification by a modified Kaiser test

• Gerald Jarre,
• Steffen Heyer,
• Elisabeth Memmel,
• Thomas Meinhardt and
• Anke Krueger

Beilstein J. Org. Chem. 2014, 10, 2729–2737, doi:10.3762/bjoc.10.288

• to primary amines. Secondary amines cannot be detected reliably and aromatic and tertiary amines do not yield positive test results either [24]. One report on the non-quantitative application of the Kaiser test on ethylene diamine functionalized nanodiamond has been reported recently [25]. For

A small azide-modified thiazole-based reporter molecule for fluorescence and mass spectrometric detection

• Stefanie Wolfram,
• Hendryk Würfel,
• Stefanie H. Habenicht,
• Christine Lembke,
• Phillipp Richter,
• Eckhard Birckner,
• Rainer Beckert and
• Georg Pohnert

Beilstein J. Org. Chem. 2014, 10, 2470–2479, doi:10.3762/bjoc.10.258

• was emitted by NBD/DDY/catalase, which is probably due to very low fluorescence quantum yields reported for NBD derivatives of primary amines in water [39]. Furthermore, NBD (9) is not suitable for standard SDS-PAGE (12% gels) as the dye smears and therefore potentially covers fluorescent signals of

Primary-tertiary diamine-catalyzed Michael addition of ketones to isatylidenemalononitrile derivatives

• Akshay Kumar and
• Swapandeep Singh Chimni

Beilstein J. Org. Chem. 2014, 10, 929–935, doi:10.3762/bjoc.10.91

• been found to catalyze a variety of carbon–carbon bond-forming reactions [25][26][27][28][29][30]. Small peptides derived from acyclic amino acids, primary-secondary diamines, Cinchona-based primary amines, and thioureas with a primary amine functionality etc., have found many successful applications

Isocyanide-based multicomponent reactions towards cyclic constrained peptidomimetics

• Gijs Koopmanschap,
• Eelco Ruijter and
• Romano V.A. Orru

Beilstein J. Org. Chem. 2014, 10, 544–598, doi:10.3762/bjoc.10.50

• subsequent 3-CR with diketene 98 and a wide variety of primary amines to afford the triazole linker. The scope of the Ugi reaction was investigated with several aliphatic and aromatic aldehydes and amines and gave the Ugi-products in good yields (34-61%). Moreover, the scope of sequential cycloaddition was

•  48). In a combined approach, Gunawan et al. also described such an Ugi-azide reaction to develop γ/δ/ε-lactam tetrazoles [126][127]. Depending on the keto-ester or acid used, an Ugi reaction with different primary amines, isocyanides and TMSN3 followed by subsequent cyclization gave either γ-, δ- or

• reported [147]. A wide variety of aldehydes, primary amines and carboxylic acids were tolerated resulting in a library of 80 different linear dipeptides. Cleavage from the carbonate resin with KOt-Bu afforded compound 176 which was converted to the methyl ester 177 using NaOMe (Scheme 54). Subsequent TFA

Silver and gold-catalyzed multicomponent reactions

• Giorgio Abbiati and
• Elisabetta Rossi

Beilstein J. Org. Chem. 2014, 10, 481–513, doi:10.3762/bjoc.10.46

• expansion of its scope to include difficult substrates such as aliphatic primary amines and ammonia, the development of highly enantioselective A3-coupling reactions with broad substrate specificity, and the incorporation of the A3-coupling reaction into tandem processes are all challenges that are expected

• as a powerful tool for the synthesis of medium-sized libraries of bioactive compounds. Thus, straightforward syntheses of 1,3-disubstituted-1,2-dihydroisoquinolines have been achieved by three-component reactions between alkynylbenzaldehydes 25 (γ-carbonylalkyne), primary amines 26 (mainly anilines

• -protons and thus allowing for an easy α-deprotonation with weak bases (Scheme 32) [86][87]. Recently, Orru’s group successfully translated the stepwise Schöllkopf–Van Leusen synthesis of dihydroimidazoles 65 in a MCR involving isocyanides 61, aldehydes 62 and primary amines 63 [88]. Initial results