Divergent Construction of Pyrazoles via Michael Addition of N‑Arylhydrazones to 1,2-Diaza-1,3-dienes

partially_open4noThe base (NaH)-promoted Michael addition of N-arylhydrazones (AHs) with 1,2-diaza-1,3-dienes (DDs) produces unprecedented β-azohydrazone adducts. Strategically, the use of AHs as acyl anion equivalents (d1 synthon) and DDs as α-electrophiles (a2 synthon) of carbonyl compounds open the way to two important classes of pyrazole compounds.embargoed_20160409Serena mantenuto; Fabio Mantellini; Orazio Attanasi; Gianfranco FaviMantenuto, Serena; Mantellini, Fabio; Attanasi, ORAZIO ANTONIO; Favi, Gianfranc

Divergent Construction of Pyrazoles via Michael Addition of <i>N</i>‑Arylhydrazones to 1,2-Diaza-1,3-dienes

The base (NaH)-promoted Michael addition of <i>N</i>-arylhydrazones (AHs) with 1,2-diaza-1,3-dienes (DDs) produces unprecedented β-azohydrazone adducts. Strategically, the use of AHs as acyl anion equivalents (<i>d</i>¹ synthon) and DDs as α-electrophiles (<i>a</i>² synthon) of carbonyl compounds open the way to two important classes of pyrazole compounds

Synthesis of Densely Functionalized 3a,4-Dihydro‑1<i>H</i>‑Pyrrolo[1,2‑<i>b</i>]Pyrazoles via Base Mediated Domino Reaction of Vinyl Malononitriles with 1,2-Diaza-1,3-dienes

A domino reaction of vinyl malononitriles (VMs) with 1,2-diaza-1,3-dienes (DDs) produce unprecedented 3a,4-dihydro-1<i>H</i>-pyrrolo[1,2-<i>b</i>]pyrazole systems in a chemo-, regio-, and stereoselective fashion. This base promoted (DIPEA) one-pot transformation involving multiple steps constructs one new C–C bond, two C–N bonds, and two new fused heterocyclic rings with total atom economy