Enantioselective reduction of ketoimines promoted by easily available (S)-proline derivatives

• Martina Bonsignore,
• Maurizio Benaglia,
• Laura Raimondi,
• Manuel Orlandi and
• Giuseppe Celentano

Beilstein J. Org. Chem. 2013, 9, 633–640, doi:10.3762/bjoc.9.71

• good yield after 18 hours. Under these conditions a modest to good level of stereoselection were observed; the best results were obtained by running the reaction in chlorinated solvents, such as dichloromethane and chloroform, where enantioselectivity up to 75% was achieved by simply performing the

Asymmetric Brønsted acid-catalyzed aza-Diels–Alder reaction of cyclic C-acylimines with cyclopentadiene

• Magnus Rueping and
• Sadiya Raja

Beilstein J. Org. Chem. 2012, 8, 1819–1824, doi:10.3762/bjoc.8.208

• was used (Table 1, entries 10 and 11). Hence, the chlorinated solvents were replaced by hexane. Interestingly, use of a 1:1 mixture of toluene and hexane afforded the corresponding product without loss of selectivity, but, as anticipated, the reaction time was longer (Table 1, entry 12). Pleasingly

Manganese dioxide mediated one-pot synthesis of methyl 9H-pyrido[3,4-b]indole-1-carboxylate: Concise synthesis of alangiobussinine

• Jessica Baiget,
• Sabin Llona-Minguez,
• Stuart Lang,
• Simon P. MacKay,
• Colin J. Suckling and
• Oliver B. Sutcliffe

Beilstein J. Org. Chem. 2011, 7, 1407–1411, doi:10.3762/bjoc.7.164

• ). Changing the solvent to chloroform showed that chlorinated solvents are compatible in the reaction (Table 1, entry c), and that the low temperature was more detrimental to the process than the nature of the solvent. The process was found to work best when 1,4-dioxane was used as the solvent, with a yield

The arene–alkene photocycloaddition

• Ursula Streit and
• Christian G. Bochet

Beilstein J. Org. Chem. 2011, 7, 525–542, doi:10.3762/bjoc.7.61

• isolated in moderate yield. Anisole photocycloaddition precursors did not afford similar tetracyclic compounds under the same irradiation conditions. However, under slightly acidic conditions (chlorinated solvents or additional p-toluenesulfonic acid) the photocycloaddition to the same compound could be

Thermal rearrangement of tert-butylsulfinamide

• Veera Reddy Arava,
• Laxminarasimhulu Gorentla and
• Pramod Kumar Dubey

Beilstein J. Org. Chem. 2011, 7, 9–12, doi:10.3762/bjoc.7.2

• above room temperature, and in chlorinated solvents they undergo rearrangement to form the more stable N-(tert-butylthio)-tert-butylsulfonamide. Keywords: chlorinated solvents; N-(tert-butylthio)-tert-butylsulfonamide; tert-butylsulfinamide; thermal rearrangement; Introduction Over the past decade, an

• room temperature and in chlorinated solvents. Experimental See Supporting Information File 1 for full experimental data. tert-Butylsulfinamide. N-(tert-butylthio)-tert-butylsulfonamide. ORTEP diagram of 3. Synthesis of acid amide. Chemical synthesis of 3. Synthesis of tert-butylsulfanyl chloride

About the activity and selectivity of less well-known metathesis catalysts during ADMET polymerizations

• Hatice Mutlu,
• Lucas Montero de Espinosa,
• Oĝuz Türünç and
• Michael A. R. Meier

Beilstein J. Org. Chem. 2010, 6, 1149–1158, doi:10.3762/bjoc.6.131

• activity of the catalyst. Furthermore, Johnson and coworkers reported that during a RCM to make a 9-membered ring, chlorinated solvents, such as 1,2-dichloroethane, inhibited olefin isomerization [25]. Grubbs and collaborators showed that catalytic amounts (10 mol %) of 1,4-benzoquinone (BQ) can prevent

Kinetics and mechanism of vanadium catalysed asymmetric cyanohydrin synthesis in propylene carbonate

• Michael North and
• Marta Omedes-Pujol

Beilstein J. Org. Chem. 2010, 6, 1043–1055, doi:10.3762/bjoc.6.119

• chlorinated solvents, optimally dichloromethane. Recently however, we showed that catalyst 2 could be used in propylene carbonate [53]. Propylene carbonate and other cyclic carbonates are starting to attract significant interest as green solvents [54][55][56][57][58][59][60][61][62][63][64], since they can be