Copper-catalyzed CuAAC/intramolecular C–H arylation sequence: Synthesis of annulated 1,2,3-triazoles

• Rajkumar Jeyachandran,
• Harish Kumar Potukuchi and
• Lutz Ackermann

Beilstein J. Org. Chem. 2012, 8, 1771–1777, doi:10.3762/bjoc.8.202

• apparatus SMP3, Barlworld Scientific; values are uncorrected. General procedure for the synthesis of triazoles 4 NaN3 (1.05 equiv), CuI (10 mol %), LiOt-Bu (2.00 equiv), alkyne 1 (1.00 equiv) and alkyl bromide 2 (1.00 equiv) were dissolved in DMF (3.0 mL) and stirred at 80 °C for 20 h. Then, H2O (50 mL) was

The application of a monolithic triphenylphosphine reagent for conducting Appel reactions in flow microreactors

• Kimberley A. Roper,
• Heiko Lange,
• Anastasios Polyzos,
• Malcolm B. Berry,
• Ian R. Baxendale and
• Steven V. Ley

Beilstein J. Org. Chem. 2011, 7, 1648–1655, doi:10.3762/bjoc.7.194

• application of this monolith to the transformation of an alkyl alcohol into the corresponding alkyl bromide by using carbon tetrabromide in the Appel reaction. In the 1960s Ramirez and co-workers reported the formation of a phosphine–methylene species when triphenylphosphine was mixed with carbon tetrabromide

Metathesis access to monocyclic iminocyclitol-based therapeutic agents

• Ileana Dragutan,
• Valerian Dragutan,
• Carmen Mitan,
• Hermanus C.M. Vosloo,
• Lionel Delaude and
• Albert Demonceau

Beilstein J. Org. Chem. 2011, 7, 699–716, doi:10.3762/bjoc.7.81

• produce the (+)-DMDP (49) and (−)-bulgecinine (50) (Scheme 8). The starting point in the synthesis of (+)-broussonetine G, 53, was the same annulated oxazolone 48 which, after conversion into the Weinreb amide 51, was coupled with the alkyl bromide substituted spiro compound 52 (Scheme 9). In fact, the

EPR and pulsed ENDOR study of intermediates from reactions of aromatic azides with group 13 metal trichlorides

• Giorgio Bencivenni,
• Riccardo Cesari,
• Daniele Nanni,
• Hassane El Mkami and
• John C. Walton

Beilstein J. Org. Chem. 2010, 6, 713–725, doi:10.3762/bjoc.6.84

• sample was analysed by EPR spectroscopy at several different temperatures. Products analysis was performed as above. Ethyl 5-azidopentanoate (9) [48] was prepared by treatment of the corresponding alkyl bromide with sodium azide in DMSO [49]; IR (νmax, CHCl3), 1718 (CO) and 2092 (N3) cm−1; 1H NMR (400

2-Phenyl- tetrahydropyrimidine- 4(1H)-ones – cyclic benzaldehyde aminals as precursors for functionalised β²-amino acids

• Markus Nahrwold,
• Arvydas Stončius,
• Anna Penner,
• Beate Neumann,
• Hans-Georg Stammler and
• Norbert Sewald

Beilstein J. Org. Chem. 2009, 5, No. 43, doi:10.3762/bjoc.5.43

• to the reaction mixture for an in situ conversion of the alkyl bromide to the alkyl iodide [48] did not increase reactivity. The alkylation reaction started to proceed only after warming the lithium enolate solution to −55 °C, but still remained incomplete after 20 h reaction time. By adding DMPU as

An expedient synthesis of 5-n-alkylresorcinols and novel 5-n-alkylresorcinol haptens

• Kirsti Parikka and
• Kristiina Wähälä

Beilstein J. Org. Chem. 2009, 5, No. 22, doi:10.3762/bjoc.5.22

• investigated using alkyl bromide, PPh3 and 6 in various organic solvents but remained unsuccessful. Mixtures of cis and trans isomers 7a–d and 8 had Z/E ratios varying from ca. 40:60 (8) to ca. 80:20 (7a, both in open and sealed vessel) according to 1H NMR and GC-MS. As the ultimate targets were the C=C

• alkyl bromide precursors are not available (Scheme 1). 5a was readily synthesised by Swern-type oxidation (see Supporting Information File 1). The Wittig reagents were poorly soluble in water. Nevertheless, functional groups enhancing their solubility, such as previously reported –COOH or PEG