In the title compound, C22H26N4O3S, the dihedral angle between the pyrazoloneand phenyl rings is 21.73 (4)°. The benzensulfono-hydrazide group adopts a gauche conformation about the N-N vector. The C-N-N-S torsion angle is -109.88 (13)°. The mol-ecule exists as the enamine tautomeric form (C=C-NH). An intra-molecular N-H⋯O=C hydrogen bond occurs. In the crystal, mol-ecules are linked by pairs o...

Enantioselective organocatalysis has emerged as a powerful synthetic paradigm that is complementary to metal-catalysed transformations and has accelerated the development of new methods to make diverse chiral molecules. The operational simplicity, ready availability of catalysts and low toxicity associated with organocatalysis makes it an attractive method to synthesise complex structures. Here...

An efficient monoclonal aldolase antibody that proceeds by an enamine mechanism was generated by reactive immunization. Here, this catalyst has been used in the total synthesis of epothilones A (1) and C (3). The starting materials for the synthesis of these molecules have been obtained by using antibody-catalyzed aldol and retro-aldol reactions. These precursors were then converted to epothilo...

The isolation and structural characterization of both aldehyde- and ketone-derived proline enaminones are reported and discussed. Crystal structures of 10 proline enamines provide information on stereochemical aspects, i.e., double bond configuration and syn- vs. anti-positioning of the carboxylate relative to the enamine double bond. Furthermore, the obtained crystal structures are compared wi...

A tandem SNAr/5-exo-trig cyclization reaction is reported that converts N-alkyl- and -arylimines derived from o-fluorobenzaldehydes into 3-amino-2,3-dihydro-2,2-diarylbenzofurans in moderate to good yields. Diarylmethoxide coupling partners serve the dual role of nucleophile in the SNAr step and catalytic base in the cyclization step. With a subset of the substrates, a further base-induced elim...

The title 2-aza-bicyclo-[2.2.2]octa-2,5-diene derivative, C(14)H(18)N(4)O, crystallized out with two independent mol-ecules with similar conformations in the asymmetric unit. In each mol-ecule, the three six-membered rings adopt boat conformations. The mol-ecules exist in the enamine form. In the crystal, mol-ecules are linked by N-H⋯O and N-H⋯N hydrogen bonds into a two-dimensional network par...

The first highly enantioselective α-fluorination of ketones using organocatalysis has been accomplished. The long-standing problem of enantioselective ketone α-fluorination via enamine activation has been overcome via high-throughput evaluation of a new library of amine catalysts. The optimal system, a primary amine functionalized Cinchona alkaloid, allows the direct and asymmetric α-fluorinati...

In the mol-ecule of the title compound, C(18)H(22)N(2)O(3), the dihydro-pyrimidinone ring adopts an envelope conformation. The dihedral angle between the phenyl ring and the mean plane through the enamine fragment is 86.04 (7)°. The mol-ecular conformation is stabilized by an intra-molecular C-H⋯O hydrogen bond. In the crystal, inter-molecular N-H⋯O hydrogen bonds link pairs of mol-ecules into ...