Recent advances in organocatalytic asymmetric aza-Michael reactions of amines and amides

• Pratibha Sharma,
• Raakhi Gupta and
• Raj K. Bansal

Beilstein J. Org. Chem. 2021, 17, 2585–2610, doi:10.3762/bjoc.17.173

• enantioselectivity (47–98% ee). The observed results were rationalized with density functional theory calculations (Table 8) [42]. 1.3 Reactions catalyzed by chiral amines He and co-workers developed heterogeneous synergistic catalysis using chiral amines SBA-15 (cat. 44), which promote aza-Michael–Henry cascade

When metal-catalyzed C–H functionalization meets visible-light photocatalysis

• Lucas Guillemard and
• Joanna Wencel-Delord

Beilstein J. Org. Chem. 2020, 16, 1754–1804, doi:10.3762/bjoc.16.147

• ; sustainable synthesis; synergistic catalysis; Introduction In recent years, the field of synthetic chemistry has witnessed a profound evolution. Indeed, due to the growing environmental awareness, organic chemists face nowadays an urgent need of developing much more sustainable and environmentally benign

• catalysis involving two catalysts and two catalytic cycles acting in a cooperative way to create a new bond, turned out to be a powerful strategy. According to a simplified representation, synergistic catalysis involves the concurrent activation of a nucleophile and an electrophile by means of two distinct

• intermediates promotes chemical transformations generally unattainable using traditional monocatalysis. However, the potential of multicatalyzed mechanisms goes far beyond the category of synergistic catalysis and the interest in this field fructified in the development of different possible scenarios. First

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

• enals and a transition metal promoting to open the 2-vinylcyclopropanes for highly regio- and enantioselective [3 + 2] cycloaddition reaction of 2-vinylcyclopropanes with α,β-unsaturated aldehydes has been developed. Keywords: [3 + 2] annulation; enals; synergistic catalysis; vinylcyclopropanes

• Johnson and Waser for the formation of chiral tetrahydrofurans (Scheme 1, reaction 1) [36][38]. Achieving a regioselective control at the C=C bond rather than at C=O in enals represents a challenge and has not been reported. Synergistic catalysis is a very important and useful strategy in organic

• synthesis by offering power for improving reaction efficiency and/or realizing impossible processes [46][47][48][49][50][51][52][53][54][55]. Recently, we developed an enantioselective addition of aldehydes to vinylpyridines and vinylarenes catalyzed by synergistic catalysis of iminium catalyst and Brønsted