This search combines search strings from the content search (i.e. "Full Text", "Author", "Title", "Abstract", or "Keywords") with "Article Type" and "Publication Date Range" using the AND operator.
Beilstein J. Org. Chem. 2016, 12, 1870–1876, doi:10.3762/bjoc.12.176
Graphical Abstract
Figure 1: Structure of guanidines 1–10.
Scheme 1: Synthesis of guanidine 10. Conditions: (a) 1 equiv HOOC-CH2-COOH, 2 equiv NH4OAc, EtOH, 78 °C, 5 h,...
Figure 2: Crystal structure of guanidine 10 as a benzoate salt. Only one of the ion pairs is shown for the sa...
Scheme 2: Reaction of anthrones and N-arylmaleimides catalyzed by guanidine 10. The guanidine deprotonates an...
Figure 3: A) Chromatogram of rac-25 after incubation with 0.1 equiv of 10 in THF at −15 °C for 64 h. The fast...
Scheme 3: Assignment of the absolute configurations by chemical correlation. The R configuration of compound ...
Beilstein J. Org. Chem. 2014, 10, 2989–2996, doi:10.3762/bjoc.10.317
Scheme 1: Synthesis of tricyclic 1,2,4-thiadiazoles 2a–c.
Figure 1: (a) and (b) representing the solid state structure of 2a with displacement ellipsoids at the 50% pr...
Scheme 2: Possible mechanistic scenarios.
Figure 2: Optimized structures of 3, TS3→5‡ and 5 at B3LYP/6-31+G*. Free energies are reported in kcal mol−1 ...
Scheme 3: DMAP assisted cyclization-I and IIa. Free energies are reported in kcal mol−1 at 25 °C referenced t...
Figure 3: Optimized geometries of 9‡ and 14‡. Distances are shown in angstrom (italics).
Beilstein J. Org. Chem. 2008, 4, No. 28, doi:10.3762/bjoc.4.28
Scheme 1: Diels-Alder reaction of anthrones 1 and maleimides 2 catalyzed by chiral Brønsted bases 4–8.
Scheme 2: Protonation states and tautomerism of C2-symmetric bisamidine 8a [6].
Scheme 3: Synthesis of C2-symmetric bisamidines 8b–c and ent-8d.
Figure 1: Kinetic measurements of 1a with 2a catalyzed by 5 mol% of 8a·H+·TFPB- (black line) and 1 mol% 8a (f...
Figure 2: Molecular structure of 3m (C: black; N: blue; O: red; Cl: green; hydrogen atoms are omitted for the...
Scheme 4: Proposed mechanism of the Diels-Alder reaction.