First chemoenzymatic stereodivergent synthesis of both enantiomers of promethazine and ethopropazine

• Paweł Borowiecki,
• Daniel Paprocki and
• Maciej Dranka

Beilstein J. Org. Chem. 2014, 10, 3038–3055, doi:10.3762/bjoc.10.322

• , which assumed usage of sodium amide (NaNH2) as a base, produced enormous amounts of byproducts, which significantly hampered both the isolation and purification procedures. The same phenomenon was observed if sodium hydride (NaH) was utilized instead of NaNH2 under similar reaction conditions, what

De novo macrolide–glycolipid macrolactone hybrids: Synthesis, structure and antibiotic activity of carbohydrate-fused macrocycles

• Richard T. Desmond,
• Anniefer N. Magpusao,
• Chris Lorenc,
• Jeremy B. Alverson,
• Nigel Priestley and
• Mark W. Peczuh

Beilstein J. Org. Chem. 2014, 10, 2215–2221, doi:10.3762/bjoc.10.229

• , the C2 and C3 hydroxy groups were converted to methyl ethers via alkylation with iodomethane in the presence of sodium hydride to give compounds 8a and 8b (3:1, 66% combined yield). At this point the α- and β-anomers could be separated by column chromatography. Each anomer was then carried through the

Second generation silver(I)-mediated imidazole base pairs

• Susanne Hensel,
• Nicole Megger,
• Kristina Schweizer and
• Jens Müller

Beilstein J. Org. Chem. 2014, 10, 2139–2144, doi:10.3762/bjoc.10.221

• obtained using synthetic procedures established previously for the non-methylated imidazole analogue (Scheme 3) [34][38]. Methylimidazole, deprotonated in situ via the addition of sodium hydride, has been reacted with Hoffer’s chloro sugar to give the p-toluoyl-protected nucleoside (1a, 1b). In the case of

Palladium-catalysed cyclisation of alkenols: Synthesis of oxaheterocycles as core intermediates of natural compounds

• Miroslav Palík,
• Jozef Kožíšek,
• Peter Koóš and
• Tibor Gracza

Beilstein J. Org. Chem. 2014, 10, 2077–2086, doi:10.3762/bjoc.10.216

• moieties in the next cyclisation step (Scheme 7). Gratifyingly, the chloromethyltetrahydrofurans 55 and 58 were both transformed into the bicyclic products 59 and 44 by treatment with sodium hydride in DMF. Also, this transformation step has approved the relative configurations of substituents on the

Convergent synthetic methodology for the construction of self-adjuvanting lipopeptide vaccines using a novel carbohydrate scaffold

• Vincent Fagan,
• Istvan Toth and
• Pavla Simerska

Beilstein J. Org. Chem. 2014, 10, 1741–1748, doi:10.3762/bjoc.10.181

• removed during work-up. The residue was alkylated with sodium hydride and propargyl bromide in dry tetrahydrofuran (THF) to give intermediate 7, which was not isolated. The methoxy ester was hydrolyzed in situ by addition of sodium hydroxide. Acid–base extraction and purification by flash chromatography

Investigations of thiol-modified phenol derivatives for the use in thiol–ene photopolymerizations

• Sebastian Reinelt,
• Monir Tabatabai,
• Urs Karl Fischer,
• Norbert Moszner,
• Andreas Utterodt and
• Helmut Ritter

Beilstein J. Org. Chem. 2014, 10, 1733–1740, doi:10.3762/bjoc.10.180

• such as sodium hydride and allyl bromide (6), which resulted in the formation of the tetra-allyl (7a) and hexa-allyl (7b) derivatives (Scheme 1). The second route for the synthesis of the allyl-modified precursors (12a–c, 15) proceeded via Claisen rearrangement of the allylaryl ethers and subsequent

Design, automated synthesis and immunological evaluation of NOD2-ligand–antigen conjugates

• Marian M. J. H. P. Willems,
• Gijs G. Zom,
• Nico Meeuwenoord,
• Ferry A. Ossendorp,
• Herman S. Overkleeft,
• Gijsbert A. van der Marel,
• Jeroen D. C. Codée and
• Dmitri V. Filippov

Beilstein J. Org. Chem. 2014, 10, 1445–1453, doi:10.3762/bjoc.10.148

• attached to the anomeric center of the glucosamine moiety using oxazoline 6 [37][38][39]. Deacetylation and subsequent installation of the benzylidene protective group then gave alcohol 9. Coupling of 9 with (S)-2-chloropropanoic acid in the presence of sodium hydride resulted in the formation of protected

Synthesis of a sucrose dimer with enone tether; a study on its functionalization

• Zbigniew Pakulski,
• Norbert Gajda,
• Magdalena Jawiczuk,
• Jadwiga Frelek,
• Piotr Cmoch and
• Sławomir Jarosz

Beilstein J. Org. Chem. 2014, 10, 1246–1254, doi:10.3762/bjoc.10.124

• . Benzylation of 11. To a solution of alcohol 11 (82 mg, 0.037 mmol) in DMF (1 mL), sodium hydride (60% suspension in mineral oil, 7 mg) was added and the mixture was stirred for 30 min at rt. Benzyl bromide (11 μL, 0.092 mmol) was added, and stirring was continued overnight. Excess of sodium hydride was

Syntheses of fluorooxindole and 2-fluoro-2-arylacetic acid derivatives from diethyl 2-fluoromalonate ester

• Antal Harsanyi,
• Graham Sandford,
• Dmitri S. Yufit and
• Judith A.K. Howard

Beilstein J. Org. Chem. 2014, 10, 1213–1219, doi:10.3762/bjoc.10.119

• ][58][59][60][61][62] or DAST [63] providing an indication of the importance of fluorooxindoles for medicinal chemistry applications. Results and Discussion Reactions of carbanions generated by the addition of sodium hydride to a solution of diethyl 2-fluoromalonate (1) in DMF with ortho

Atherton–Todd reaction: mechanism, scope and applications

• Stéphanie S. Le Corre,
• Mathieu Berchel,
• Hélène Couthon-Gourvès,
• Jean-Pierre Haelters and
• Paul-Alain Jaffrès

Beilstein J. Org. Chem. 2014, 10, 1166–1196, doi:10.3762/bjoc.10.117

• specifically the first step (reaction of dialkyl phosphite with carbon tetrachloride and a base) by using CPG as an analytical tool. Triethylamine or sodium hydride was used as base. With sodium hydride the deprotonation occurs in a preliminary step to produce sodium dialkyl phosphite. All these attempts were

• (a solvent with the capacity to trap any traces of carbene) produced the same conversion rate. One exception to this last observation was found when the experimental conditions combined both the use of strict aprotic conditions (use of sodium hydride for the deprotonation of phosphite) and dimethyl

• when triethylamine was replaced with sodium hydride as a base, while all other parameters were identical. These results indicated that the carbene pathway is unlikely to occur under the classical conditions of the Atherton–Todd reaction (dialkyl phosphite, trialkylamine, alkyl- or dialkylamine and

Preparation of phosphines through C–P bond formation

• Iris Wauters,
• Wouter Debrouwer and
• Christian V. Stevens

Beilstein J. Org. Chem. 2014, 10, 1064–1096, doi:10.3762/bjoc.10.106

• presence of K2CO3 or KOAc favored a good stereoselectivity in contrast to K3PO4 or DBU. Sodium hydride or Ag2CO3 promoted retention of configuration. The mechanism of the reaction was studied by Gaumont et al. through isolation of the reactive intermediate [174]. Lipshutz et al. reported the palladium

Molecular recognition of isomeric protonated amino acid esters monitored by ESI-mass spectrometry

• Andrea Liesenfeld and
• Arne Lützen

Beilstein J. Org. Chem. 2014, 10, 825–831, doi:10.3762/bjoc.10.78

• ethynylated and arylated alcohols 8 in 95% yield and 9 in 87% yield over both steps, respectively. Finally, deprotonation by sodium hydride and reaction with tosylated 18-crown-6 derivative 10 [17][18] derived from commercially available (1,4,7,10,13,16-hexaoxacyclooctadecan-2-yl)methanol afforded the desired

Phosphinate-containing heterocycles: A mini-review

• Olivier Berger and
• Jean-Luc Montchamp

Beilstein J. Org. Chem. 2014, 10, 732–740, doi:10.3762/bjoc.10.67

• synthesis of 1,3-oxaphospholes 20a–f (Scheme 9) by reacting chloroalkylphosphinic or phosphonic chlorides 18 with malonic diester 19 in the presence of two equivalents of sodium hydride [23][24]. 1,3-Oxaphospholes 20a–f were obtained in yields up to 70%. 1-Aza-3-phospha-6-oxabicyclo[3.3.0]octanes The

The Flögel-three-component reaction with dicarboxylic acids – an approach to bis(β-alkoxy-β-ketoenamides) for the synthesis of complex pyridine and pyrimidine derivatives

• Mrinal K. Bera,
• Moisés Domínguez,
• Paul Hommes and
• Hans-Ulrich Reissig

Beilstein J. Org. Chem. 2014, 10, 394–404, doi:10.3762/bjoc.10.37

• was observed under the applied conditions, affording in 18% yield 4-hydroxypyridine 18b with a retained β-ketoenamide moiety. Treatment of compounds 16, 18a and 18b with sodium hydride followed by nonafluorobutanesulfonyl fluoride (NfF) provided the corresponding sulfonates 17, 19 and 20 in yields in

Synthesis of five- and six-membered cyclic organic peroxides: Key transformations into peroxide ring-retaining products

• Alexander O. Terent'ev,
• Dmitry A. Borisov,
• Vera A. Vil’ and
• Valery M. Dembitsky

Beilstein J. Org. Chem. 2014, 10, 34–114, doi:10.3762/bjoc.10.6

• , neither sodium hydride nor sodium salt 183 cleave the ozonide ring to a substantial degree. The resulting 1,2,4-trioxolanes 188 and 189 exhibit high in vitro antimalarial activity comparable with that of artemisinin and in vivo even higher activity than that of artemisinin [93]. Aminoquinoline-containing

N,N'-(Hexane-1,6-diyl)bis(4-methyl-N-(oxiran-2-ylmethyl)benzenesulfonamide): Synthesis via cyclodextrin mediated N-alkylation in aqueous solution and further Prilezhaev epoxidation

• Julian Fischer,
• Simon Millan and
• Helmut Ritter

Beilstein J. Org. Chem. 2013, 9, 2834–2840, doi:10.3762/bjoc.9.318

• apparatus was set under constant nitrogen-flow and 17.2 mmol of sodium hydride were added. Afterwards, the suspension was stirred for 2 h and subsequently, 35 mmol of allyl bromide (4), which was filtrated through neutral aluminium oxide, was added dropwise. The resulting mixture was stirred at 50 °C for 18

A scalable synthesis of the (S)-4-(tert-butyl)-2-(pyridin-2-yl)-4,5-dihydrooxazole ((S)-t-BuPyOx) ligand

• Hideki Shimizu,
• Jeffrey C. Holder and
• Brian M. Stoltz

Beilstein J. Org. Chem. 2013, 9, 1637–1642, doi:10.3762/bjoc.9.187

• adventitious moisture for more than one week. Furthermore, chloride 11 proved to be a superior cyclization substrate. A series of bases were screened. Organic amine bases (Table 2, entries 4,5) and sodium hydride (Table 2, entry 6) provided inadequate conversion and low yields, whereas hydroxide and alkoxide

Mechanistic studies on the CAN-mediated intramolecular cyclization of δ-aryl-β-dicarbonyl compounds

• Brian M. Casey,
• Dhandapani V. Sadasivam and
• Robert A. Flowers II

Beilstein J. Org. Chem. 2013, 9, 1472–1479, doi:10.3762/bjoc.9.167

• GC–MS instrument. A Satellite FTIR from Thermo-Mattson was used to obtain IR spectra. LC–HRMS data were recorded at the Mass Spectrometry Facility at Notre Dame University. General procedure for the synthesis of δ-aryl-β-dicarbonyl compounds 1a–j. Sodium hydride (11 mmol) was suspended in 25 mL of

α-Bromodiazoacetamides – a new class of diazo compounds for catalyst-free, ambient temperature intramolecular C–H insertion reactions

• Åsmund Kaupang and
• Tore Bonge-Hansen

Beilstein J. Org. Chem. 2013, 9, 1407–1413, doi:10.3762/bjoc.9.157

• introduced by our group, both employing an N-halosuccinimide as the halogen source in combination with either the amidine base 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) or sodium hydride (NaH). In these reports, the obtained α-halodiazoacetates and α-halodiazophosphonates were successfully applied in

Synthesis of guanidinium–sulfonimide ion pairs: towards novel ionic liquid crystals

• Martin Butschies,
• Manuel M. Neidhardt,
• Markus Mansueto,
• Sabine Laschat and
• Stefan Tussetschläger

Beilstein J. Org. Chem. 2013, 9, 1093–1101, doi:10.3762/bjoc.9.121

• , 2.91 mmol) was given to a suspension of sodium hydride (333 mg, 8.31 mmol) in abs DMF (10 mL) and the mixture was stirred for 1 h. After cooling to 0 °C a solution of 4-(dodecyloxy)benzenesulfonylchloride (4, 1.00 g, 2.77 mmol) in abs THF (5 mL) was added dropwise and the reaction mixture was warmed to

Methylidynetrisphosphonates: Promising C₁ building block for the design of phosphate mimetics

• Vadim D. Romanenko and
• Valery P. Kukhar

Beilstein J. Org. Chem. 2013, 9, 991–1001, doi:10.3762/bjoc.9.114

• phosphite in the presence of sodium hydride gives the triphosphonate 18 (Scheme 9). Note that bisphosphonate 16 is also available by the reaction 4-hydroxy-3,5-di-tert-butylbenzaldehyde with triethyl phosphite in the presence of malonic ester (yield 53%) [32]. This reaction mode takes place also for the

Preparation and ring-opening reactions of N-diphenylphosphinyl vinyl aziridines

• Ashley N. Jarvis,
• Andrew B. McLaren,
• Helen M. I. Osborn and
• Joseph Sweeney

Beilstein J. Org. Chem. 2013, 9, 852–859, doi:10.3762/bjoc.9.98

• with ethyl acetate/light petroleum (1:1) as an eluent. Palladium-catalyzed ring-opening with malonate: To diethyl malonate (typically 0.3–0.6 mmol, 1.1 equiv) in THF (1.5 mL), at room temperature, under argon, was added sodium hydride (1.1 equiv), and the colourless solution was left to stir for 30 min

• (typically 0.3–0.7 mmol, 1.1 equiv) in THF (2 mL), at room temperature, under argon, was added sodium hydride (1.1 equiv), and the suspension was left to stir for 30 min. Pd(PPh3)4 (3 mol %) was added to the reaction mixture, and the dark orange suspension was further stirred for twenty five minutes. A

Direct alkenylation of indolin-2-ones by 6-aryl-4-methylthio-2H-pyran-2-one-3-carbonitriles: a novel approach

• Sandeep Kumar,
• Ramendra Pratap,
• Abhinav Kumar,
• Brijesh Kumar,
• Vishnu K. Tandon and
• Vishnu Ji Ram

Beilstein J. Org. Chem. 2013, 9, 809–817, doi:10.3762/bjoc.9.92

• Information File 2). General procedure for the synthesis of alkenylindoline-2-ones 8y A mixture of sodium hydride (2.1 mmol), indolin-2-one (4, 1.1 mmol) and lactone 3 (1.0 mmol) in dry THF (10 mL) was heated under reflux for 4–5 h. The excess of THF was removed under reduced pressure, and the reaction

• afford products 8ya–8yj (the analytical data and spectra are given in Supporting Information File 1 and Supporting Information File 2). General procedure for the synthesis of 1-aryl-3-(sec-amino)-5H-dibenzo[d,f][1,3]diazepin-6(7H)-one (10) A mixture of lactone (9, 1.0 mmol) sodium hydride (2.1 mmol), and

Some aspects of radical chemistry in the assembly of complex molecular architectures

• Béatrice Quiclet-Sire and
• Samir Z. Zard

Beilstein J. Org. Chem. 2013, 9, 557–576, doi:10.3762/bjoc.9.61

• the reductive dexanthylation of adduct 102 derived from 2-allylcyclohexanone, does not undergo an intramolecular HWE condensation to give a cyclooctene derivative upon treatment with sodium hydride. The formation of the cyclooctene ring is not very favourable and cannot compete with the simple aldol

Thermotropic and lyotropic behaviour of new liquid-crystalline materials with different hydrophilic groups: synthesis and mesomorphic properties

• Alexej Bubnov,
• Miroslav Kašpar,
• Věra Hamplová,
• Ute Dawin and
• Frank Giesselmann

Beilstein J. Org. Chem. 2013, 9, 425–436, doi:10.3762/bjoc.9.45

• , ArOCH2CH2O), 3.90–3.60 (m, 10H, CH2O), 3.45 (t, 2H, CH2Br), 1.90, 1.60, 1.30 (m, 3H, CH2C*H), 1.02 (d, 3H, CH3), 0.97 (t, 3H, CH3). Sodium hydride (0.1 mol) was slowly added to a solution of 0.2 mol of 1,1,1- tris(hydroxymethyl)ethane (pentaglycerine) in 0.25 L dry dimethylformamide. After one hour of