Cupreines and cupreidines: an established class of bifunctional cinchona organocatalysts

• Laura A. Bryant,
• Rossana Fanelli and
• Alexander J. A. Cobb

Beilstein J. Org. Chem. 2016, 12, 429–443, doi:10.3762/bjoc.12.46

• asymmetric organocatalysis. This fascinating class of bifunctional catalyst offers a genuine alternative to the more commonly used thiourea systems and because of the different spacing between the functional groups, can control enantioselectivity where other organocatalysts have failed. In the main, this

• their derivatives in asymmetric organocatalysis over the last five years or so [13][14]. The review is organized by reaction type, beginning with the Morita–Baylis–Hillman process – one of the first reactions to utilize 6’-OH-cinchona alkaloid derivatives in asymmetric organocatalysis. The focus will

Organocatalytic asymmetric Henry reaction of 1H-pyrrole-2,3-diones with bifunctional amine-thiourea catalysts bearing multiple hydrogen-bond donors

• Ming-Liang Zhang,
• Deng-Feng Yue,
• Zhen-Hua Wang,
• Yuan Luo,
• Xiao-Ying Xu,
• Xiao-Mei Zhang and
• Wei-Cheng Yuan

Beilstein J. Org. Chem. 2016, 12, 295–300, doi:10.3762/bjoc.12.31

• -pyrrol-2(3H)-ones bearing quaternary stereocenters were obtained in acceptable yield (up to 75%) and enantioselectivity (up to 73% ee). Keywords: asymmetric catalysis; bifunctional catalysts; Henry reaction; organocatalysis; 1H-pyrrole-2,3-diones; Introduction Asymmetric organocatalysis has been

Multivalent polyglycerol supported imidazolidin-4-one organocatalysts for enantioselective Friedel–Crafts alkylations

• Tommaso Pecchioli,
• Manoj Kumar Muthyala,
• Rainer Haag and
• Mathias Christmann

Beilstein J. Org. Chem. 2015, 11, 730–738, doi:10.3762/bjoc.11.83

• support in asymmetric organocatalysis. The use of chiral imidazolidinones in organocatalysis has been extensively reported for a wide range of enantioselective reactions involving α,β-unsaturated aldehydes, such as the Diels–Alder reactions [50], 1,3-dipolar cycloadditions [51] and Friedel–Crafts

Chemoselective O-acylation of hydroxyamino acids and amino alcohols under acidic reaction conditions: History, scope and applications

• Tor E. Kristensen

Beilstein J. Org. Chem. 2015, 11, 446–468, doi:10.3762/bjoc.11.51

• asymmetric organocatalysis In the previous section, the developmental history of acidic acylation methodologies for chemoselective O-acylation of hydroxyamino acids has been chronicled, from its inception in the early 1940s until the 1990s. In particular, the identification and application of suitable

• asymmetric organocatalysis picked up momentum quite rapidly. Through a series of disclosures, during the time period from 2010 to 2012, Xiangkai Fu and co-workers detailed the preparation of amphiphilic organocatalysts from serine, threonine and cysteine by acidic O-acylation, as well as their use in

• asymmetric organocatalysis [54][55][56][57][58][59][60][61]. Chemoselective O-acylation of serine, threonine and cysteine in CF3CO2H with a range of acyl chlorides, followed by crystallization of the product directly from the reaction mixture by addition of Et2O, furnished a comprehensive collection of

A combined continuous microflow photochemistry and asymmetric organocatalysis approach for the enantioselective synthesis of tetrahydroquinolines

• Erli Sugiono and
• Magnus Rueping

Beilstein J. Org. Chem. 2013, 9, 2457–2462, doi:10.3762/bjoc.9.284

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

• methods for the development of environmentally benign chemical transformations. Recently, the use of these mechanochemical techniques in asymmetric organocatalysis has increased. This review highlights the progress in asymmetric organocatalytic reactions assisted by mechanochemical techniques. Keywords

• amplified in recent times. In this regard, catalytic asymmetric synthesis involving the use of chiral organocatalysts has emerged as a powerful tool from the infancy to the maturity of asymmetric organocatalysis [13][14][15][16][17][18][19][20][21][22][23][24][25][26]. The use of organocatalysts for

• , which helps in the easy isolation of products. Besides the significant progress in the application of mechanochemical techniques in asymmetric organocatalysis, there exists a lot of scope for other asymmetric reactions ranging from simple carbon–carbon, and carbon–heteroatom bond formation to more

Synthesis of chiral sulfoximine-based thioureas and their application in asymmetric organocatalysis

• Marcus Frings,
• Isabelle Thomé and
• Carsten Bolm

Beilstein J. Org. Chem. 2012, 8, 1443–1451, doi:10.3762/bjoc.8.164

• hydrogenations and carbon–carbon bond formations [34][35][36]. During the past decade, asymmetric organocatalysis had a tremendous impact on synthetic organic chemistry [37][38][39][40][41]. Yet, this field of research continues to grow, and the quest for new organic molecules which efficiently catalyze

• (-like) catalysts with S-stereogenic sulfonimidoyl substituents are unknown. Herein, we present our first results concerning synthetic approaches towards such molecules and describe preliminary studies of two applications in asymmetric organocatalysis. Results and Discussion Our investigations began with

• leading to a dihydropyrimidinone. In the future we aim to expand the scope of the chiral sulfonimidoyl-containing thiourea framework and hope to find more applications of these interesting molecules in asymmetric organocatalysis. General structure of sulfoximines 1 and one of the enantiomers of S-methyl-S

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

Organocatalytic asymmetric allylic amination of Morita–Baylis–Hillman carbonates of isatins

• Hang Zhang,
• Shan-Jun Zhang,
• Qing-Qing Zhou,
• Lin Dong and
• Ying-Chun Chen

Beilstein J. Org. Chem. 2012, 8, 1241–1245, doi:10.3762/bjoc.8.139

• yields (up to 97%). Keywords: allylic amination; asymmetric organocatalysis; Morita–Baylis–Hillman carbonates; 2-oxindoles; quaternary chiral center; Introduction Chiral 3-amino-2-oxindoles are versatile and useful units for the preparation of natural products and drug candidates, such as the

Enantioselective synthesis of tricyclic amino acid derivatives based on a rigid 4-azatricyclo[5.2.1.0^2,6]decane skeleton

• Matthias Breuning,
• Tobias Häuser,
• Christian Mehler,
• Christian Däschlein,
• Carsten Strohmann,
• Andreas Oechsner and
• Holger Braunschweig

Beilstein J. Org. Chem. 2009, 5, No. 81, doi:10.3762/bjoc.5.81

• β-turn-inducing building blocks in peptidomimetics and for chiral auxiliaries in asymmetric organocatalysis. Keywords: amino acid; enantioselective synthesis; norbornane; polycyclic compounds; pyrrolidine; Introduction Unnatural amino acids with a rigid bowl-shaped backbone have received