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Search for "organocatalytic" in Full Text gives 186 result(s) in Beilstein Journal of Organic Chemistry.
Development of the titanium–TADDOLate-catalyzed asymmetric fluorination of β-ketoesters
Beilstein J. Org. Chem. 2011, 7, 1421–1435, doi:10.3762/bjoc.7.166
- -catalyzed asymmetric fluorinations were discovered by others and ourselves, based on complexes of Pd(II) [46], Cu(II) [47][48][49], Ni(II) [48][50] and Ru(II) [51] as catalysts [4][51]. In parallel, organocatalytic asymmetric electrophilic fluorination of carbonyl compounds by means of phase-transfer
Multicomponent synthesis of artificial nucleases and their RNase and DNase activity
Beilstein J. Org. Chem. 2011, 7, 1135–1140, doi:10.3762/bjoc.7.131
- organocatalytic three-component modification of the Ugi reaction, recently developed by List et al. [25]. The reaction results in diamines 4, thus avoiding the acid residue removal stage. The starting diisocyanides 3 were obtained in good overall yields from commercially available diamines containing 6, 7, 8, 10
Recent advances in the gold-catalyzed additions to C–C multiple bonds
Beilstein J. Org. Chem. 2011, 7, 897–936, doi:10.3762/bjoc.7.103
- malononitriles 375 and N-Boc-protected imines 374 (Scheme 60) [176]. In the alkyne hydroamination (which is based on a bifunctional organocatalytic Mannich-type reaction, subsequent gold-catalyzed alkyne hydroamination and isomerization) thiourea-based hydrogen bonding organocatalyst 373 and PPh3AuNTf2 proved to
Asymmetric synthesis of tertiary thiols and thioethers
Beilstein J. Org. Chem. 2011, 7, 582–595, doi:10.3762/bjoc.7.68
- of the enantiomers of hindered enone 46 by addition, oxidation and elimination of a sulfenic acid under basic conditions (Scheme 18) [45]. Xiao and co-workers developed an organocatalytic process for the addition of thiols to nitroalkenes [46]. Using thiourea organocatalyst 48, conjugate addition of
- of enone 46. Organocatalytic conjugate addition to nitroalkenes 49. Preparation of β-amino acid 54. Sulfur migration within oxazolidine-2-thiones 56. Preparation of thiols 62 by self-regeneration of stereocentres. Synthesis of (5R)-thiolactomycin. Preparation of tertiary thiols and thioethers via α
Shelf-stable electrophilic trifluoromethylating reagents: A brief historical perspective
Beilstein J. Org. Chem. 2010, 6, No. 65, doi:10.3762/bjoc.6.65
- of alcohols with 35 in the presence of 1 equiv of Zn(NTf2)2. Formation of trifluoromethyl sulfonates from sulfonic acids and 35. Organocatalytic α-trifluoromethylation of aldehydes with 37. Synthesis of reagent 42 and mechanism of trifluoromethylation. Trifluoromethylation of β-ketoesters and
Enantioselective synthesis of tricyclic amino acid derivatives based on a rigid 4-azatricyclo[5.2.1.02,6]decane skeleton
Beilstein J. Org. Chem. 2009, 5, No. 81, doi:10.3762/bjoc.5.81
- (five steps). The required endo-orientation of the acetic acid moiety in 8a•HCl was confirmed by the X-ray structure of the corresponding free base 8a•MeOH (Figure 4). A first evaluation of the bowl-shaped amino acid derivatives 7 and 8 in standard organocatalytic aldol and Mannich reactions showed that
Asymmetric reactions in continuous flow
Beilstein J. Org. Chem. 2009, 5, No. 19, doi:10.3762/bjoc.5.19
- significantly higher when compared to a carousel-type reactor typically used for parallel synthesis. Organocatalytic asymmetric aldol reactions in microflow devices were recently reported by our laboratory [15]. The aldol condensation of various aromatic aldehydes with acetone was carried out at higher
C2- symmetric bisamidines: Chiral Brønsted bases catalysing the Diels- Alder reaction of anthrones
Beilstein J. Org. Chem. 2008, 4, No. 28, doi:10.3762/bjoc.4.28
- bisamidine-mediated organocatalytic transformations. Kinetic measurements of 1a with 2a catalyzed by 5 mol% of 8a·H+·TFPB- (black line) and 1 mol% 8a (free base; red line). Molecular structure of 3m (C: black; N: blue; O: red; Cl: green; hydrogen atoms are omitted for the sake of clarity). Diels-Alder
DBFOX- Ph/metal complexes: Evaluation as catalysts for enantioselective fluorination of 3-(2-arylacetyl)-2-thiazolidinones
Beilstein J. Org. Chem. 2008, 4, No. 16, doi:10.3762/bjoc.4.16
- reactions. Stoichiometric approaches based on cinchona alkaloid/Selectfluor® combinations [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32], chiral ligand/metal-catalyzed [33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56][57] or organocatalytic [58
The first organocatalytic carbonyl- ene reaction: isomerisation- free C-C bond formations catalysed by H-bonding thio- ureas
Beilstein J. Org. Chem. 2007, 3, No. 24, doi:10.1186/1860-5397-3-24
- interest in hydrogen bond mediated catalysis,[11] we have investigated thioureas as H-bonding additives for organocatalytic carbonyl ene reactions and report these results here. Despite the explosive growth in organocatalytic reactions in recent years, [12][13][14][15][16] this represents, to the best of
- our knowledge, the first example of an organocatalytic carbonyl ene reaction. [17] Findings We first carried out a thermal ene reaction of α-methyl styrene 1 with ethyl trifluoropyruvate under microwave heating to produce racemic product 3 (Scheme 1). This reaction was accompanied by several side
- % catalyst. Lower catalyst loadings required longer reaction times. Thus, in common with most organocatalytic procedures, turnover frequency is low. In order to explore if an asymmetric variant of this reaction was possible, we elected to employ a chiral thio-urea. It is almost certain that these reactions
Beilstein Journal of Organic Chemistry
Beilstein J. Org. Chem. 2005, 1, No. 1, doi:10.1186/1860-5397-1-1
- still to be discovered. Four years ago, the Nobel prize in chemistry celebrated chemists' achievements in asymmetric catalysis – and even since then the face of catalysis is changing, with for example metathesis and organocatalytic methods constantly breaking into new areas. Synthesis is changing too
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