Robust C–C bonded porous networks with chemically designed functionalities for improved CO₂ capture from flue gas

• Damien Thirion,
• Joo S. Lee,
• Ercan Özdemir and
• Cafer T. Yavuz

Beilstein J. Org. Chem. 2016, 12, 2274–2279, doi:10.3762/bjoc.12.220

• through metal-free Knoevenagel nitrile–aldol condensation, namely the covalent organic polymer, COP-156 and 157. COP-156, due to high specific surface area (650 m2/g) and easily interchangeable nitrile groups, was modified post-synthetically into free amine- or amidoxime-containing networks. The modified

• formation of these structures do not allow obtaining free nitrile or amine functionalities. The most used strategy to install available functional groups on porous materials is through post-modification, which often requires several steps and harsh conditions, and yields low porosity [12][13]. The

• Knoevenagel condensation of benzyl nitriles and aldehydes produces C–C bonded products with labile nitrile functionalities. In fact, nitrile groups have been shown in porous polymers (particularly in polymers of intrinsic microporosity (PIMs)) to be good precursors to several functionalities like carboxylic

Elongated and substituted triazine-based tricarboxylic acid linkers for MOFs

• Arne Klinkebiel,
• Ole Beyer,
• Barbara Malawko and
• Ulrich Lüning

Beilstein J. Org. Chem. 2016, 12, 2267–2273, doi:10.3762/bjoc.12.219

• substituted) with two equivalents of an unsubstituted nitrile. Triple Suzuki coupling of the cores 3 with suitable phenyl- and biphenylboronic acid derivatives provided elongated tricarboxylic acid linkers as carboxylic acids 17 and 20 or their esters 16 and 19. Reduction of the nitro group and cleavage of

• trimerization of respective nitriles [13]. Unsymmetric 1,3,5-triazines 3 can be made by combining one equivalent of an acid chloride with two equivalents of a nitrile [14][15][16] (for a recently described alternative access to unsymmetrical 1,3,5-triazines; see [17]). In the presence of a suitable Lewis acid

Regiocontroled Pd-catalysed C5-arylation of 3-substituted thiophene derivatives using a bromo-substituent as blocking group

• Mariem Brahim,
• Hamed Ben Ammar,
• Jean-François Soulé and
• Henri Doucet

Beilstein J. Org. Chem. 2016, 12, 2197–2203, doi:10.3762/bjoc.12.210

• yield of 85% of 10 was obtained with 4-bromo-2-(trifluoromethyl)nitrobenzene. Then, the reactivity of a set of ortho-substituted aryl bromides was examined. Bromobenzene containing nitro, nitrile or formyl ortho-substituents afforded the C5-arylated thiophenes 11–13 in 71–84% yields. Finally, 3

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

• treatment of a nitronate anion with oxalyl chloride were recently published [61][62] (Scheme 6). Acylnitroso compounds are generally prepared and used in situ due to their extremely reactive nature and the conditions have been summarized previously [16]. These include the oxidation of nitrile oxides [63] or

One-pot synthesis of 4′-alkyl-4-cyanobiaryls on the basis of the terephthalonitrile dianion and neutral aromatic nitrile cross-coupling

• Roman Yu. Peshkov,
• Elena V. Panteleeva,
• Wang Chunyan,
• Evgeny V. Tretyakov and
• Vitalij D. Shteingarts

Beilstein J. Org. Chem. 2016, 12, 1577–1584, doi:10.3762/bjoc.12.153

• method is based on biaryl cross-coupling between the sodium salt of the terephthalonitrile dianion and a neutral aromatic nitrile in liquid ammonia, and successive alkylation of the long-lived anionic intermediate with alkyl bromides. The reaction is compatible with benzonitriles that contain methyl

• Discussion The suggested one-pot synthesis of alkylcyanobiaryls 5 comprises consecutive generation of terephthalonitrile dianion (12–) [30][31][32] by the addition of metallic sodium to a suspension of dinitrile 1 in liquid ammonia, treating of the thus formed 12− salt with a twofold excess of nitrile 2

• of the cyanophenyl fragment of dianion 12− into the para-position of nitrile 2a with the formation of cyclohexadienyl anion 3 after rapid decyanation of the primary cross-coupling dianionic product. Next, the alkylation of intermediate 3 occurs at the position ipso to the cyano group. This

Molecular weight control in organochromium olefin polymerization catalysis by hemilabile ligand–metal interactions

• Stefan Mark,
• Hubert Wadepohl and
• Markus Enders

Beilstein J. Org. Chem. 2016, 12, 1372–1379, doi:10.3762/bjoc.12.131

• function is covalently bonded have been reported [37][38][39]. Some of those donors bind strongly, others weakly, to a particular transition metal ion. Examples, which are related to the work described here, are Cp ligands with olefinic [40][41][42][43][44][45][46][47][48][49][50][51][52] or with a nitrile

• do not interact with the coordinatively saturated chromium centers. The coordination ability of the chosen donors D range from very weak (organofluorine) to medium (olefinic or aryl, respectively) and strong (nitrile). Activation with methylaluminoxane (MAO) leads to the formation of monomethyl

• organofluorine substituent is connected by a side arm with suitable length. In addition to that we choose side arms with olefinic groups, a benzyl unit and a stronger nitrile donor group, respectively. The synthesis of the new ligand derivatives and the corresponding Cr complexes follows known procedures (Scheme

Multicomponent reactions: A simple and efficient route to heterocyclic phosphonates

• Mohammad Haji

Beilstein J. Org. Chem. 2016, 12, 1269–1301, doi:10.3762/bjoc.12.121

• prepared via this efficient method. One of the best strategies is based on the use of Bestmann–Ohira reagent (BOR) as the 1,3-dipole precursor. Smietana et al. accomplished a related three-component reaction with different aldehydes 211, nitrile derivatives 212 and dimethyldiazomethylphosphonate 213 to

• adduct 214, resulting from condensation of aldehydes 211 and nitrile derivatives 212, lead to cyclo-adduct intermediates 216 which cyclize to phosphorylated pyrazoles 217. In this way, a one-pot three-component reaction of aldehydes 218, methyl ketones 219 and the Bestmann–Ohira reagent has been

Cationic Pd(II)-catalyzed C–H activation/cross-coupling reactions at room temperature: synthetic and mechanistic studies

• Takashi Nishikata,
• Alexander R. Abela,
• Shenlin Huang and
• Bruce H. Lipshutz

Beilstein J. Org. Chem. 2016, 12, 1040–1064, doi:10.3762/bjoc.12.99

• arylureas at room temperature. A commercially available catalyst [Pd(MeCN)4](BF4)2 or a nitrile-free cationic palladium(II) complex generated in situ from the reaction of Pd(OAc)2 and HBF4, effectively catalyzes C–H activation/cross-coupling reactions between aryl iodides, arylboronic acids and acrylates

• been previously observed in the coupling reactions of aryl iodides (in which even 40 mol % of MeCN was enough to almost completely shut down the reaction) [121]. In a cationic palladium(II) complex-catalyzed 1,4-addition of arylsilane, the nitrile-free cationic Pd(II) catalyst was much more effective

• coordinating ability as a ligand on cationic palladium. On the other hand, when nitrile-free conditions were applied to urea 1f, with in situ-generated palladacycle (from Pd(OAc)2 and HBF4; Figure 8), followed by addition of the usual reagents, each reaction proceeded to give the anticipated acrylated/arylated

1H-Imidazol-4(5H)-ones and thiazol-4(5H)-ones as emerging pronucleophiles in asymmetric catalysis

• Antonia Mielgo and
• Claudio Palomo

Beilstein J. Org. Chem. 2016, 12, 918–936, doi:10.3762/bjoc.12.90

• formation [82] (Scheme 7b,2). 2.1 Synthesis of thiazol-4(5H)-ones 2 Thiazol-4(5H)-ones 2 can be easily prepared starting from the corresponding α-mercaptocarboxylic acid and nitrile. Treatment of both with triethylamine in refluxing ethanol [83] provides the expected thiazol-4(5H)-ones as yellow/green

Synthesis of Xenia diterpenoids and related metabolites isolated from marine organisms

• Tatjana Huber,
• Lara Weisheit and
• Thomas Magauer

Beilstein J. Org. Chem. 2015, 11, 2521–2539, doi:10.3762/bjoc.11.273

• rearrangement [41] to afford an aldehyde that was converted to dimethylacetal 60. The following epoxidation proceeded with good stereoselectivity (α/β ≈ 11:1) and the regioselective opening of the epoxide moiety using lithium cyanide afforded a β-hydroxy nitrile in a trans-diaxial arrangement. Under basic

• conditions, the configuration of the nitrile group at C2 was inverted, furnishing the thermodynamically more stable 61. Nitrile 61 was then converted to lactol 62 in seven further steps. Next, the cyclononene ring of 63 was constructed via a Grob fragmentation of 6,6,5-tricycle 62, affording the bicyclic

Syntheses of 2-substituted 1-amino-4-bromoanthraquinones (bromaminic acid analogues) – precursors for dyes and drugs

• Enas M. Malik,
• Younis Baqi and
• Christa E. Müller

Beilstein J. Org. Chem. 2015, 11, 2326–2333, doi:10.3762/bjoc.11.253

• -substituted derivative which, under different reaction conditions, yielded the corresponding carbaldehyde, carboxylic acid, and nitrile derivatives. The latter was further reacted to obtain 1-amino-2-tetrazolylanthraquinone. Subsequent bromination using bromine in DMF led to the corresponding bromaminic acid

• Shie et al., compound 9 was treated with sodium azide and zinc bromide under MW irradiation [62], however, the desired product 1-amino-4-bromo-2-tetrazolylanthraquinone (10, Scheme 2) could not be obtained. Following an alternative procedure, nitrile 9 was reacted with sodium azide in a mixture of N

• ) using the same oxidative amination procedure as described above. A total of six equivalents of iodine was needed to produce the desired product 12 in high yield (Scheme 3, Table 1). The method of Gutmann et al. was subsequently applied to the conversion of nitrile 12 to the corresponding 1-amino-2

Synthesis of D-fructose-derived spirocyclic 2-substituted-2-oxazoline ribosides

• Madhuri Vangala and
• Ganesh P. Shinde

Beilstein J. Org. Chem. 2015, 11, 2289–2296, doi:10.3762/bjoc.11.249

• oxacarbenium-ion intermediate by a nitrile and subsequent intramolecular nucleophilic attack of the vicinal C2 ether or a free hydroxy group [32][33][34]. Such glycooxazolines are exploited for the generation of N-glycan structures [35]. In O-glycosylation reactions, an oxacarbenium-ion intermediate interacts

• with nitrile solvents, providing a transient α,β-glycosyl nitrilium species that could produce an oxazolinium intermediate through the participation of the vicinal oxygen atom. In 1981, Pavia and co-workers proposed the formation of uncharacterized oxazolinium from glycosyl hemiacetal in acetonitrile

• were eventually found to be unstable. Later in 2004, García Fernández and co-workers elegantly showed the formation of fused and spiroglycooxazolines from D-fructose [37]. More recently, Mong and co-workers synthesized fused glucopyranose oxazolines in nitrile solvents from thioglycoside donors and

Recent advances in copper-catalyzed C–H bond amidation

• Jie-Ping Wan and
• Yanfeng Jing

Beilstein J. Org. Chem. 2015, 11, 2209–2222, doi:10.3762/bjoc.11.240

• chloride/anhydrides [6][7][8][9][10][11], nitrile hydrolysis [12][13][14][15][16], Goldberg C–N cross coupling reaction [17], aldehyde/ketone amidation [18][19][20][21][22][23], the transamidation [24][25][26][27][28][29], and oxime rearrangement [30][31][32][33], to name only a few. It is obvious that the

Chiral Cu(II)-catalyzed enantioselective β-borylation of α,β-unsaturated nitriles in water

• Lei Zhu,
• Taku Kitanosono,
• Pengyu Xu and
• Shū Kobayashi

Beilstein J. Org. Chem. 2015, 11, 2007–2011, doi:10.3762/bjoc.11.217

• the synthesis of biologically interesting compounds and of other materials. In particular, compounds with a nitrile group in the β-position with respect to the boron moiety represent an important subset of organoboron intermediates because these compounds contain two functional groups. Their C–B

• linkage can be transformed into C–O, C–N, as well as into C–C bonds, while retaining stereogenic centers [1][2][3][4]. The nitrile group can be transformed into a range of functional groups, such as amides [5], carboxylic acids [6], aldehydes [7], esters [8], alcohols [9], and amines [10

• catalysis, which has been reported recently for asymmetric boron conjugate addition, is characterized by the effective and thermodynamically stable catalysis in water. Furthermore, a broad range of α,β-unsaturated acceptors, including one example of an α,β-unsaturated nitrile, are applicable, and the

Copper-catalyzed aerobic radical C–C bond cleavage of N–H ketimines

• Ya Lin Tnay,
• Gim Yean Ang and
• Shunsuke Chiba

Beilstein J. Org. Chem. 2015, 11, 1933–1943, doi:10.3762/bjoc.11.209

• having a strained cyclobutane ring did not form the desired oxaspirocyclohexadienone (Scheme 6). Instead, γ-bromoketone 8e was isolated in 44% yield along with nitrile 5a in 80% yield. The formation of γ-bromoketone 8e is most likely caused by radical ring opening from the transient cyclobutoxy radical I

Stereochemistry of ring-opening/cross metathesis reactions of exo- and endo-7-oxabicyclo[2.2.1]hept-5-ene-2-carbonitriles with allyl alcohol and allyl acetate

• Piotr Wałejko,
• Michał Dąbrowski,
• Lech Szczepaniak,
• Jacek W. Morzycki and
• Stanisław Witkowski

Beilstein J. Org. Chem. 2015, 11, 1893–1901, doi:10.3762/bjoc.11.204

• geometry Z/E was reported. It should be emphasized that in the presence of a nitrile group an efficient metathetic transformation is difficult to carry out due to a competitive complexation of Ru by the nitrile group [22]. The influence of the reaction conditions on the distribution of the type A products

• products (1-2 and 1-3). While the reaction of endo-nitrile 2 with alcohol 4 proceeded with lower Z/E selectivity (1.5:1) (Table 1, entries 13–15), the exo-isomer 1 reacted without any stereoselectivity (Table 1, entries 7–9). It is worth to note that the reactions of nitriles 1 and 2 promoted by the Grubbs

Cross metathesis of unsaturated epoxides for the synthesis of polyfunctional building blocks

• Meriem K. Abderrezak,
• Kristýna Šichová,
• Nancy Dominguez-Boblett,
• Antoine Dupé,
• Zahia Kabouche,
• Christian Bruneau and
• Cédric Fischmeister

Beilstein J. Org. Chem. 2015, 11, 1876–1880, doi:10.3762/bjoc.11.201

• electron- deficient olefin cross metathesis partner has received attention for the synthesis of polymer precursors. For instance, we have reported the reduction of the nitrile functional group into primary amine [22] and the reduction of the formyl group into alcohol [23][24]. Herein, we focused on the

• by intramolecular trans-esterification from 6, 7 and 8, as well as cyclic amines by intramolecular cyclization involving primary amine resulting from hydrogenation of the nitrile functionality in 5. All these aspects will be further developed in our group. Cross metathesis of 1 with methyl acrylate

Influence of bulky yet flexible N-heterocyclic carbene ligands in gold catalysis

• Alba Collado,
• Scott R. Patrick,
• Danila Gasperini,
• Sebastien Meiries and
• Steven P. Nolan

Beilstein J. Org. Chem. 2015, 11, 1809–1814, doi:10.3762/bjoc.11.196

• selected: alkyne hydration, nitrile hydration, and the synthesis of homoallylic ketones. To place these results into context, [Au(IPr)(NTf2)] (10) [46] was also tested under the same conditions. Alkyne hydration Alkyne hydration is an attractive transformation to generate ketones from alkynes with high

• obtained in all cases (Table 1, entries 5–8). However, the best conversion was observed when complex 10 bearing the IPr ligand was used (Table 1, entry 5). Complexes 7–9 afforded lower conversions, with [Au(IHept)(NTf2)] (8) being the most efficient amongst them (Table 1, entries 6–9). Nitrile hydration

• characterised. The impact of varying the length of the alkyl chain of the ligands in gold-promoted transformations has been explored. All gold complexes were shown to be active in water inclusive reactions (alkyne and nitrile hydration) and in the synthesis of homoallylic ketones from allylic alcohols and

Pyridinoacridine alkaloids of marine origin: NMR and MS spectral data, synthesis, biosynthesis and biological activity

• Louis P. Sandjo,
• Victor Kuete and
• Maique W. Biavatti

Beilstein J. Org. Chem. 2015, 11, 1667–1699, doi:10.3762/bjoc.11.183

• function by first hydrolyzing the amide function to the corresponding amine following by the preparation of the diazonium and substitution of the diazonium function with a nitrile group. The latter was then converted to a carboxylic group under strongly acidic conditions. The acid derivative was treated

Development of variously functionalized nitrile oxides

• Haruyasu Asahara,
• Keita Arikiyo and
• Nagatoshi Nishiwaki

Beilstein J. Org. Chem. 2015, 11, 1241–1245, doi:10.3762/bjoc.11.138

• -functionalized isoxazole derivatives. Since the amide was prepared by the cycloaddition reaction of ethynylbenzene and N-methylcarbamoylnitrile oxide, the nitrile oxide served as the equivalent of the nitrile oxides bearing a variety of functional groups such as carboxy, alkoxycarbonyl, carbamoyl, acyl and

• formyl moieties. Keywords: acylnitrile oxide; amide; formylnitrile oxide; functionalized nitrile oxide; Weinreb amide; Introduction Nitrile oxides are valuable synthetic synthons for the construction of heterocyclic compounds by cycloaddition reactions, which lead to the formation of two bonds in a

• single experimental step [1][2]. In addition, cycloadducts serve as precursors of polyfunctionalized compounds by ring opening reaction followed by N–O bond fission [2][3]. Hence, functionalized nitrile oxides are clearly useful for the preparation of more complex systems. However, because the precursors

The synthesis of active pharmaceutical ingredients (APIs) using continuous flow chemistry

• Marcus Baumann and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2015, 11, 1194–1219, doi:10.3762/bjoc.11.134

• and chloroacetyl chloride. The crude nitrile product 81 was then collected in a batch vessel and isolated in pure form after crystallisation and washing with n-heptane. Alkylation of 81 with the corresponding amino-adamantane derivate in the presence of excess K2CO3 following an existing batch

Thiazole formation through a modified Gewald reaction

• Carl J. Mallia,
• Lukas Englert,
• Gary C. Walter and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2015, 11, 875–883, doi:10.3762/bjoc.11.98

• general, substrates which have an α-methylene adjacent to the nitrile group gave 2-aminothiophene (Scheme 1) whilst those that possessed an α-methine yielded the corresponding 2-substituted thiazole. Originally, reactions were performed using conventional heating, however, to allow for a wider temperature

• conversion and isolated yield (58%) with tetramethylethylenediamine (TMEDA) also giving a respectable yield of 50% (Table 1, entries 1 and 10). The stronger guanidine bases 1,1,3,3-tetramethylguanidine (TMG) and 1,8-diazabicycloundec-7-ene (DBU) both gave full consumption of the nitrile starting material

• its condensation with the aldehyde component (generated from 10), which inhibits the transformation. In addition, a sulfonic acid bound resin (QP-SA) was also trialled as an additive but showed no conversion allowing full recovery of the starting nitrile (see later discussion on mechanism). These

Trifluoromethyl-substituted tetrathiafulvalenes

• Olivier Jeannin,
• Frédéric Barrière and
• Marc Fourmigué

Beilstein J. Org. Chem. 2015, 11, 647–658, doi:10.3762/bjoc.11.73

• the deformation of the unsymmetrically substituted dithiole rings, when bearing one, or two different EWG, and attributed to the mesomeric effect of ester or nitrile groups, is not notably modified or counter-balanced by the introduction of a neighboring trifluoromethyl group. DFT calculations confirm

• these observations and also show that the low energy HOMO–LUMO absorption band found in nitrile or ester-substituted TTFs is not found in TTF-CF3, where, as in TTF itself, the low energy absorption band is essentially attributable to a HOMO→LUMO + 1 transition. Despite relatively high oxidation

• tetrathiafulvalenes functionalized by electron-withdrawing groups (EWG) are less documented, essentially because the presence of such substituents as halogen, acyl, ester, amide or nitrile on the TTF redox core dramatically increases its oxidation potential and destabilizes the radical cation form. This strong anodic

TTFs nonsymmetrically fused with alkylthiophenic moieties

• Rafaela A. L. Silva,
• Bruno J. C. Vieira,
• Marta M. Andrade,
• Isabel C. Santos,
• Sandra Rabaça,
• Dulce Belo and
• Manuel Almeida

Beilstein J. Org. Chem. 2015, 11, 628–637, doi:10.3762/bjoc.11.71

• cyanoethyl groups, by C–H…N hydrogen bonds and S…N short contacts. There are no interactions between A and D molecules and the stacks are out-of-registry; 2) on the other side the stacking interaction is between the nitrile groups of A and the methyl groups of D, and is mediated by a weak C–H…N hydrogen bond

Cross-dehydrogenative coupling for the intermolecular C–O bond formation

• Igor B. Krylov,
• Vera A. Vil’ and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2015, 11, 92–146, doi:10.3762/bjoc.11.13