Synthesis of heterocycles based on azomethine ylides from α-amino acids (or amines) and carbonyl compounds

• Ekaterina V. Berezhnaya,
• Alexander I. Ponyaev,
• Vitali M. Boitsov and
• Alexander V. Stepakov

Beilstein J. Org. Chem. 2026, 22, 705–741, doi:10.3762/bjoc.22.55

• amines) and to demonstrate their synthetic potential using a number of examples. The main strategies for synthesizing pyrrolidine derivatives via asymmetric and non-asymmetric 1,3-dipolar cycloaddition of azomethine ylides derived from cyclic and acyclic amino acids or amino esters with various carbonyl

Ligand effects, solvent cooperation, and large kinetic solvent deuterium isotope effects in gold(I)-catalyzed intramolecular alkene hydroamination

• Ruichen Lan,
• Brock Yager,
• Yoonsun Jee,
• Cynthia S. Day and
• Amanda C. Jones

Beilstein J. Org. Chem. 2024, 20, 479–496, doi:10.3762/bjoc.20.43

• catalyzed by triflic acid and the gold π-activation pathway was questioned [26]. Nevertheless, advancements in gold-catalyzed reactions continued to be achieved. In particular, successful asymmetric methods were reported in short time after initially reported non-asymmetric methods, specifically Kojima’s

Synergistic chiral iminium and palladium catalysis: Highly regio- and enantioselective [3 + 2] annulation reaction of 2-vinylcyclopropanes with enals

• Haipan Zhu,
• Peile Du,
• Jianjun Li,
• Ziyang Liao,
• Guohua Liu,
• Hao Li and
• Wei Wang

Beilstein J. Org. Chem. 2016, 12, 1340–1347, doi:10.3762/bjoc.12.127

• important challenges. To the best of our knowledge, so far merely two catalyst manifolds have been realized to effect the transformations with C=C double bonds instead of C=O in the α,β-unsaturated systems. Tsuji described the first organometallic promoted non-asymmetric reaction between D–A cyclopropanes

Enantioselective additions of copper acetylides to cyclic iminium and oxocarbenium ions

• Jixin Liu,
• Srimoyee Dasgupta and
• Mary P. Watson

Beilstein J. Org. Chem. 2015, 11, 2696–2706, doi:10.3762/bjoc.11.290

• –77%), but poor enantioselectivities (1–11% ee). However, the use of activated acetylenes provides a functional group handle for elaboration, which the authors demonstrate in the preparation of indolizidine 223AB. Building on their initial discovery of a non-asymmetric, copper-catalyzed, three

Mechanochemistry assisted asymmetric organocatalysis: A sustainable approach

• Pankaj Chauhan and
• Swapandeep Singh Chimni

Beilstein J. Org. Chem. 2012, 8, 2132–2141, doi:10.3762/bjoc.8.240

• synthetic organic chemistry has increased considerably, due to the need for development of sustainable methodologies, and has been widely used in solvent-free non-asymmetric transformations. On the other hand, demands for the development of stereoselective synthesis of organic molecules have noticeably

Organocatalytic C–H activation reactions

• Subhas Chandra Pan

Beilstein J. Org. Chem. 2012, 8, 1374–1384, doi:10.3762/bjoc.8.159

• non-asymmetric and asymmetric C–H activation reactions mediated by organocatalysts are discussed in this review. Keywords: asymmetric; C–H activation; non-asymmetric; organocatalysis; organocatalytic; Introduction C–H activation reactions have recently been found to be a powerful method for the

• transformations will not be covered in this review. Review Organocatalytic sp3 C–H bond activation reactions Non-asymmetric variants tert-Amino effect: The “tert-amino effect” refers to the ring-closure reactions that proceed by redox processes for C–C and C–X bond formation within conjugated systems [7][8][9

• non-asymmetric version of the reaction using pyrrolidine-TFA as catalyst in acetonitrile. High yields (67–98%) and moderate to good diastereoselectivities (59:41 to 80:20) were obtained for amine donors of different ring size [24]. After successfully performing the non-asymmetric synthesis of