Pd-catalyzed sp-sp³cross-coupling of benzyl bromides using lithium acetylides

Organolithium-based cross-coupling reactions have emerged as an indispensable method to construct C-C bonds. These transformations have proven particularly useful for the direct and fast coupling of various organolithium reagents (sp, sp2, and sp3) with aromatic (pseudo) halides (sp2). Here we present an efficient method for the cross-coupling of benzyl bromides (sp3) with lithium acetylides (sp). The reaction proceeds within 10 min at room temperature and can be performed in the presence of organolithium-sensitive functional groups such as esters, nitriles, amides and boronic esters. The potential application of the methodology is demonstrated in the preparation of key intermediates used in pharmaceuticals, chemical biology and natural products

Groene keuzes voor de Nederlandse basisindustrie: Klimaatneutrale productie in een circulaire economie

Dit rapport schetst hoe de Nederlandse basisindustrie in 2050 klimaatneutraal en circulair kan produceren. Het is gebaseerd op discussies binnen het Sustainable Industry Lab vanaf medio 2021. De transitie van de basisindustrie is uitdagend, maar de ligging aan de Noordzee en het netwerk van industriële bedrijven, toeleveranciers en kennisinstellingen, maken het plausibel en wenselijk dat Nederland een flinke basisindustrie behoudt. Dat vraagt echter om keuzes, waarover de meningen uiteen lopen. We schetsen daarom ook hoe verschillende sociaal-maatschappelijke toekomstbeelden deze keuzes beïnvloeden

Organogelation enables fast organolithium cross-coupling reactions in air

C-C bond formation based on palladium-catalysed cross-coupling reactions using organolithium reagents has seen major breakthroughs in the past decade. However, the use of inert conditions, as well as slow addition of the organolithium species, is generally required. Here we describe the Pd-catalysed cross-coupling of C36H74-gelated organolithium reagents with aryl bromides. The reaction proceeds in 5 min at room temperature, while eliminating the previously required slow addition, and strict use of inert atmosphere. Crucially, the use of organolithium gels facilitates handling, and offers a tremendously increased process safety, which is illustrated by a gram-scale transformation that does not require any extraordinary safety precautions

Palladium-catalysed cross-coupling of lithium acetylides

The incorporation of alkynes into organic molecules is one of the most valuable transformations for the formation of C–C bonds and provides a versatile handle for further modifications. The Sonogashira cross-coupling of acetylenes holds a prominent position among the suite of catalytic cross-coupling reactions that are key to modern synthesis. Here we present a method that is complementary to the Sonogashira reaction, demonstrating cross-coupling of lithium acetylides with aryl bromides. The reactions take place under ambient conditions with short reaction times, affording the corresponding aryl acetylenes in good to excellent yields while displaying a remarkable functional group tolerance for an organolithium reaction, allowing the presence of a variety of organolithium-sensitive carbonyl functionalities. This developed cross-coupling methodology offers ample opportunities to access a wide variety of acetylenes, as is illustrated by the facile preparation of key intermediates for chemical biology and optoelectronic materials. [Figure not available: see fulltext.

Fragmented Self and Fragmented Responsibility: Pasiphae in Euripides\u2019 Cretans

This chapter analyses the particularly complex representation of responsibility and selfhood present in the speech of Pasiphae in Euripides\u2019 Cretans, in which the queen defends her act of falling in love with the bull. The chapter shows how Pasiphae is able to dissociate herself completely from her past actions by appealing to divine intervention, the role of her husband Minos, and an understanding of human morality and motivation that is rooted in hedonistic principles. Pasiphae\u2019s defence thus relies on a concept of the fragmentation of the self that reveals her as one of Euripides\u2019 most philosophically sophisticated female speakers