Lewis acid mediated reactions of organocopper reagents. Entrainment in the conjugate addition to .alpha.,.beta.-unsaturated ketones, esters, and acids via the RCu.cntdot.BF3 system

Abstract

flask was heated under nitrogen for 2 h at 160-170 °C (oil bath temperature), allowed to cool, and refrigerated overnight. The product was collected by filtration, washed successively with DMF, ethanol, and ether, and dried in vacuo to give 0.14 g (47%) of a yellow powder, mp > 300 °C. The analytical sample was prepared by recrystallization from DMF: IR (KBr) 3440,3385,3340, 2220, 1700 (br), 1665,1635,1600 cm"1. The compound was too insoluble in Me2SO or TFA for determination of its NMR spectrum.

Katalytische enantioselektive konjugierte 1,6‐Addition von Grignard‐Reagentien an lineare Dienoate

“…(für Dienoate) sowie Krause (für Enine) haben gezeigt, dass eine Abstimmung der Elektronendichte am Kupferkatalysator eine regioselektive 1,4- [5] oder 1,6-Addition [6][7][8] ermöglicht. Bei der enantioselektiven konjugierten Addition an größere Dienone und Dienoate wurden bislang nur geringe Fortschritte erzielt.…”

Synthesis of new N-norbornylimide substituted amide derivatives, their reductive Heck and domino Heck reactions

“…27 Thereafter, compound 2 was obtained from the reaction of hydrazonium chloride and compound 1 in toluene at room temperature. 28 We continued to prepare the optically active norbornenylimide substituted acid 3 from 1 using Amos' procedure.…”

Organocuprates Initiated Anionic Living Polymerization of tert-Butyl Methacrylate

“…The initiators also effectively initiated the polymerization of TBA and styrene to afford polymers with very broad MWDs (Mw/Mn= 1.7-2.7) (runs [13][14][15][16]24). The cuprate initiators, however, could not initiate the polymerizations of methyl crotonate, and diethyl and diisopropyl fumarates, irrespective of the presence or absence of Lewis acid (runs [17][18][19][20][21][22]. The feature to be noted in the polymerizations of methacrylates other than TBMA is that polymerizations proceeded with relatively higher initiator efficiency (e.g., for MMA, f = 27% at 0°C, run 4), implying that the other cuprates presented in eq 3-5 may also be active species for the polymerization of MMA.…”