Preparation of Functionalized Arylmagnesium Reagents Bearing an o-Chloromethyl Group

Highly Functionalized Organomagnesium Reagents Prepared through Halogen–Metal Exchange

“…Treatment of the benzylic chloride 52 with iPrMgBr in THF (À30 8C, 1 h) furnishes the corresponding Grignard reagent 53, which reacts at À10 8C with phenyl isocyanate to give the functionalized N-phenylphthalimide derivative 54 in 75 % yield. [33] The reaction of the related aryl magnesium species 55 with ethyl 2-(bromomethyl)acrylate [34] furnishes the polyfunctionalized product 56 in 83 % yield. Subsequent treatment of 56 with benzylamine in the presence of K 2 CO 3 in refluxing THF provides the benzoazepine 57 in 75 % yield.…”

“…Subsequent treatment of 56 with benzylamine in the presence of K 2 CO 3 in refluxing THF provides the benzoazepine 57 in 75 % yield. [33] In strong contrast to the corresponding lithium reagent, which is stable only at À100 8C, [35] the magnesium species 55 is stable for several hours at À30 8C. The reagent 55 was recently transmetallated to the boronic acid 58 by the reaction with B(OiPr) 3 and subsequent hydrolysis.…”

Synthese hoch funktionalisierter Organomagnesiumreagentien durch Halogen‐Metall‐Austausch

“…Die Einführung elektrophiler funktioneller Gruppen in ortho ‐Stellung zur Kohlenstoff‐Magnesium‐Bindung führt zu Ringschlussreaktionen durch zwei sequenzielle Alkylierungen (Schema ). Die Reaktion des Benzylchlorids 52 mit i PrMgBr in THF (−30 °C, 1 h) liefert die Grignard‐Verbindung 53 , die bei −10 °C mit Phenylisocyanat in 75 % Ausbeute zum funktionalisierten N ‐Phenylphthalimidderivat 54 umgesetzt werden kann 33. Die Reaktion der verwandten Arylmagnesiumspezies 55 mit 2‐(Brommethyl)acrylsäureethylester liefert das polyfunktionalisierte Produkt 56 in 83 % Ausbeute 34.…”

High-yielding synthesis of 1-isoindolinone derivatives via palladium-catalysed cycloaminocarbonylation

“…3 Several methodologies, such as condensation of u-aminoalkanols with phthalide, the reactions of 2-(bromomethyl)benzoate with primary amines and the monoreduction of phthalimide followed by alkylation were used for the synthesis of the basic 1-isoindolinone skeleton. Further synthetic approaches, such as acid-mediated intramolecular cationic cyclization involving N-acyliminium species, 4 rearrangement of ortho-phthalaldehyde with urea and thiourea analogs under the catalysis of trimethylchlorosilane, 5 the synthesis of non-racemic 1-isoindolinone targets by using g-lactam derivatives as N-aciliminium ion precursors, 6 reaction of arylmagnesium reagents bearing o-chloromethyl group with isocyanates, 7 and via oxidative radical cyclization, 8 for the synthesis of the 1-isoindolinone bicyclic system were published.…”