Mechanisms for radical reactions initiating from N-hydroxyphthalimide esters

• Carlos R. Azpilcueta-Nicolas and
• Jean-Philip Lumb

Beilstein J. Org. Chem. 2024, 20, 346–378, doi:10.3762/bjoc.20.35

• reaction classes, we discuss the utility of the NHPI esters, with an eye towards their continued development in complexity-generating transformations. Keywords: decarboxylative couplings; mechanisms; NHPI-esters; radical reactions; Introduction The historical challenges of using radicals in synthetic

• -decarboxylative couplings with 4-cyanopyridines [105] (Scheme 29A). In the mechanism of the latter transformation, pyridine 137 also serves as a catalyst, generating the crucial pyridine-boryl radical 138 via reaction with B2pin2 (Scheme 29B). The proposed species 138 induces the reductive fragmentation of active

• utility is frequently restricted due to various challenges, such as RAE decomposition and a limited aryl halide scope. In recent years, the Baran lab has made progress in enhancing the practicality and applicability of electrochemically driven decarboxylative couplings involving NHPI esters and aryl

Heterogeneous photocatalysis in flow chemical reactors

• Christopher G. Thomson,
• Ai-Lan Lee and
• Filipe Vilela

Beilstein J. Org. Chem. 2020, 16, 1495–1549, doi:10.3762/bjoc.16.125

Decarboxylative and dehydrative coupling of dienoic acids and pentadienyl alcohols to form 1,3,6,8-tetraenes

• Ghina’a I. Abu Deiab,
• Mohammed H. Al-Huniti,
• I. F. Dempsey Hyatt,
• Emma E. Nagy,
• Kristen E. Gettys,
• Sommayah S. Sayed,
• Christine M. Joliat,
• Paige E. Daniel,
• Rupa M. Vummalaneni,
• Andrew T. Morehead Jr,
• Andrew L. Sargent and
• Mitchell P. Croatt

Beilstein J. Org. Chem. 2017, 13, 384–392, doi:10.3762/bjoc.13.41

• . Prior and current decarboxylative couplings. Esters examined in the decarboxylation reaction. Possible mechanistic pathways. Optimization of the one-component decarboxylation reaction.a Optimization of the two-component decarboxylation reaction.a Substrate scope for the two-component decarboxylation

Practical synthesis of aryl-2-methyl-3-butyn-2-ols from aryl bromides via conventional and decarboxylative copper-free Sonogashira coupling reactions

• Andrea Caporale,
• Stefano Tartaggia,
• Andrea Castellin and
• Ottorino De Lucchi

Beilstein J. Org. Chem. 2014, 10, 384–393, doi:10.3762/bjoc.10.36

• bromides rather than expensive iodides and using 4 or propiolic acid rather than TMS-acetylene as inexpensive alkyne sources are described. Keywords: alkynes; decarboxylative couplings; Erlotinib; palladium; propiolic acid; Introduction The Sonogashira coupling reaction of aryl or alkenyl halides with

• presence of a Cu/Pd bimetallic catalyst, followed by the basic cleavage of the protecting group [42][43][44][45][46]. Terminal alkynes are often used as starting materials for the synthesis of disubstituted acetylenes through a second coupling process with another aryl halide. Decarboxylative couplings

Iron-catalyzed decarboxylative alkenylation of cycloalkanes with arylvinyl carboxylic acids via a radical process

• Jincan Zhao,
• Hong Fang,
• Jianlin Han and
• Yi Pan

Beilstein J. Org. Chem. 2013, 9, 1718–1723, doi:10.3762/bjoc.9.197

• ][68]. Our group was surprised to find that low-cost Fe(acac)3 could catalyze the direct alkenylation of cyclohexane sp3 C–H bonds by decarboxylative couplings with high efficiency. Results and Discussion We initiated our investigation by reacting cinnamic acid (1a, 0.3 mmol) with cyclohexane (2a, 2 mL

Palladium-catalyzed substitution of (coumarinyl)methyl acetates with C-, N-, and S-nucleophiles

• Kalicharan Chattopadhyay,
• Erik Fenster,
• Alexander J. Grenning and
• Jon A. Tunge

Beilstein J. Org. Chem. 2012, 8, 1200–1207, doi:10.3762/bjoc.8.133

• hydroxymethylcoumarins, we chose to investigate their decarboxylative couplings of enolates. We have previously shown that decarboxylative benzylation (DcB) is a useful method for the addition of less-stabilized enolate anions to a benzyl functionality [46][53][54][55]. Thus, we envisioned being able to add various

Pd-catalyzed decarboxylative Heck vinylation of 2-nitrobenzoates in the presence of CuF₂

• Lukas J. Gooßen,
• Bettina Zimmermann and
• Thomas Knauber

Beilstein J. Org. Chem. 2010, 6, No. 43, doi:10.3762/bjoc.6.43

• excess molecular sieves in NMP at 120 °C, yielding the vinyl arene 3aa in 89%. Based on our mechanistic studies of this and other decarboxylative couplings, we propose the mechanism detailed in Scheme 1. In the first step, the benzoate decarboxylates with formation of an aryl metal species. In contrast

• -position gave unsatisfactory results. Interestingly, substrates with 2-methoxy or 2-fluoro substituents, which are highly reactive in other decarboxylative couplings mediated by palladium alone, gave low yields in this process. Taking into account that 2-nitrobenzoates are among the best substrates for