Chiral aminocyclopentene-based cycloaddition strategies to bicyclic [3.3.0] rings

Regio- and Stereoselective Synthesis of Functionalized Cyclopentene Derivatives via Mizoroki–Heck Reactions

“…However, such olefin addition reactions of Vince lactam resulted in difficult to separate mixtures of regioisomers . Instead, we envisioned that an α,β-unsaturated cyclopentene ester of class B , which is readily available from (+)-Vince lactam, should allow regioselective conjugate addition of carbon nucleophiles. We also hoped to retain the high facial selectivity observed with Vince lactam by adorning the remote amino functionality of B with bulky protecting groups.…”

Diastereoselective 1,4-Conjugate Addition of Alkyl Cuprates to Methyl Cyclopent-1-enecarboxylates

“…13 C NMR (126 MHz, 90 °C, DMSO): δ 28.6, 29.9, 35.6, 37. (7). A dry 100 L reactor was charged with CuI (1880 g, 9.87 mol) followed by the addition of anhydrous THF (21 L).…”

“…We had some support for a high π-facial selectivity since good results were recently reported starting from an analogous α,βunsaturated ester but using other nucleophiles. 7 In the subsequent protonation step, nonselective protonation of the enolate due to steric hindrance of the newly created stereogenic center would give the undesired 1S,2R,4R epimers of 5 and 6.…”

“…Even though the distance from the reacting center to the Boc-protected aminomethyl substituent is remote, we hoped that sufficient shielding of the Si face would result in a diastereoselectivity good enough for large-scale preparations to give, after protonation, compounds 5 and 6 as the major diastereomers. We had some support for a high π-facial selectivity since good results were recently reported starting from an analogous α,β-unsaturated ester but using other nucleophiles . In the subsequent protonation step, nonselective protonation of the enolate due to steric hindrance of the newly created stereogenic center would give the undesired 1 S ,2 R ,4 R epimers of 5 and 6 .…”

Ruthenium Oxide Hexacyanoferrate as an Effective Electrode Modifier for Amperometric Detection of Iodate and Hydrogen Peroxide

“…5,7 The preparation of hexacyanoferrate films with ruthenium also has been reported. Generally, the formed films on the elec-trode surface exhibit high electrocatalytic activity in the cathodic reduction of H 2 O 2 12 and anodic oxidation of ethyl alcohol, 13,14 isopropyl alcohol, 13 L-cysteine, 13 epinephrine, 15 ranitidine, 16 hydrazine, 17 deoxyguanosine, 18 ascorbic acid, 13,15 uric acid, 15 sulfite. 19 New type mixed-valent ruthenium oxide/hexacyanoruthenate film modified electrodes were applied successfully for electrocatalytic oxidation of NADH, dopamine, SO 3 2-, S 2 O 3 2and hydrazine.…”