Enolates ambushed – asymmetric tandem conjugate addition and subsequent enolate trapping with conventional and less traditional electrophiles

• Péter Kisszékelyi and
• Radovan Šebesta

Beilstein J. Org. Chem. 2023, 19, 593–634, doi:10.3762/bjoc.19.44

• the transient iminium species 68 to afford the corresponding aminomethylation products 69 (Scheme 18) [50]. As seen from Table 2, the diastereoselectivities were somewhat compromised compared to what one can expect from the reactions of cyclic enolates. This erosion was likely caused by Lewis acid

• asymmetric conjugate addition/aminomethylation followed by an oxidation to install the exocyclic double bond. The enone 226 was isolated in 61% yield and 91% ee. Paclitaxel (taxol) is a highly successful chemotherapy medication that can be isolated from the Pacific jew tree (Taxus brevifolia), however

On the application of 3d metals for C–H activation toward bioactive compounds: The key step for the synthesis of silver bullets

• Renato L. Carvalho,
• Amanda S. de Miranda,
• Mateus P. Nunes,
• Roberto S. Gomes,
• Guilherme A. M. Jardim and
• Eufrânio N. da Silva Júnior

Beilstein J. Org. Chem. 2021, 17, 1849–1938, doi:10.3762/bjoc.17.126

• present in the natural product bismurrayafoline E (36) [105], an alkaloid found in the leaves of Murraya koeniggi (Scheme 13D) [106]. The oxidative formation of carbon–carbon bonds mediated by vanadium has been reported as a method for the aminomethylation of arenes and heteroarenes. The so far described

• heteroaromatic electrophilic substitution and a non-radical pathway. An aminomethylation of the heteroaromatic ring with N-methylmorpholine-N-oxide catalyzed by VO(aca)2 reported by Mitchell and co-workers [109], however, was found to undergo with a regioselective outcome incompatible to an electrophilic

Recent advances on the transition-metal-catalyzed synthesis of imidazopyridines: an updated coverage

• Gagandeep Kour Reen,
• Ashok Kumar and
• Pratibha Sharma

Beilstein J. Org. Chem. 2019, 15, 1612–1704, doi:10.3762/bjoc.15.165

• ) complex 64, which on reductive elimination gave the final product 62 (Scheme 22). Also, Irina V. Rassokhina and others have employed Cu(OAc)2 for the synthesis of imidazo[1,2-a]pyridines under aerobic conditions (Scheme 23) [114]. They have performed aminomethylation and cycloisomerization of propiolates

Aminomethylation/hydrogenolysis as an alternative to direct methylation of metalated isoquinolines – a novel total synthesis of the alkaloid 7-hydroxy-6-methoxy-1-methylisoquinoline

• Benedikt C. Melzer,
• Jan G. Felber and
• Franz Bracher

Beilstein J. Org. Chem. 2018, 14, 130–134, doi:10.3762/bjoc.14.8

• , after quaternization with iodomethane, is easily converted into the desired 1-methylisoquinoline by hydrogenolysis of both the benzylamine and benzyl ether groups. Keywords: alkaloid; aminomethylation; hydrogenolysis; isoquinoline; metalation; methylation; Introduction The isoquinoline ring system has

• alkaloid 7-hydroxy-6-methoxy-1-methylisoquinoline (1), but should also be of value for the synthesis of other 1-methylisoquinolines. We could demonstrate that the aminomethylation of metalated arenes with Eschenmoser’s salt followed by hydrogenolytic cleavage is a highly attractive alternative to direct

1-Imidoalkylphosphonium salts with modulated C_α–P⁺ bond strength: synthesis and application as new active α-imidoalkylating agents

• Jakub Adamek,
• Roman Mazurkiewicz,
• Anna Węgrzyk and
• Karol Erfurt

Beilstein J. Org. Chem. 2017, 13, 1446–1455, doi:10.3762/bjoc.13.142

• facilitates the cleavage of the highly polar Cα–P+ bond. Keywords: N-(1-arylalkyl)imides; α-imidoalkylating agents; imidoalkylation reactions; 1-imidoalkylphosphonium salts; Tscherniac–Einhorn-type reaction; Introduction The aminomethylation of C–H acidic compounds by the condensation of non-enolizable

Stereoselective synthesis of fused tetrahydroquinazolines through one-pot double [3 + 2] dipolar cycloadditions followed by [5 + 1] annulation

• Xiaofeng Zhang,
• Kenny Pham,
• Shuai Liu,
• Marc Legris,
• Alex Muthengi,
• Jerry P. Jasinski and
• Wei Zhang

Beilstein J. Org. Chem. 2016, 12, 2204–2210, doi:10.3762/bjoc.12.211

• , NH 03435, USA 10.3762/bjoc.12.211 Abstract The one-pot [3 + 2] cycloaddition of an azomethine ylide with a maleimide followed by another [3 + 2] cycloaddition of an azide with the second maleimide gives a 1,5-diamino intermediate which is used for a sequential aminomethylation reaction with

• ] anulation has been developed for the synthesis of fused-tetrahydroquinazolines as single diastereomers. The formation of triazoles from the second [3 + 2] cycloaddition readily affords denitrogenated 1,5-diamino compounds which are good substrates for aminomethylation with formaldehyde through a [5 + 1

The chemistry of bisallenes

• Henning Hopf and
• Georgios Markopoulos

Beilstein J. Org. Chem. 2012, 8, 1936–1998, doi:10.3762/bjoc.8.225

Recent advances in direct C–H arylation: Methodology, selectivity and mechanism in oxazole series

• Cécile Verrier,
• Pierrik Lassalas,
• Laure Théveau,
• Guy Quéguiner,
• François Trécourt,
• Francis Marsais and
• Christophe Hoarau

Beilstein J. Org. Chem. 2011, 7, 1584–1601, doi:10.3762/bjoc.7.187

• , aminomethylation, sulfuration, oxygenation). However, aryllithiums can rarely be directly involved in transition-metal-catalyzed cross-coupling reactions and are usually transformed into organometallic fragments suitable for efficient Negishi, Stille, Suzuki–Miyaura, and Hiyama cross-coupling reactions [1][2