Steric inhibition to cyclization of .beta.-keto amides to indeno[1,2,3-de]quinolinones and related compounds

Divergent Synthesis of α,α‐Dihaloamides through α,α‐Dihalogenation of β‐Oxo Amides by Using N‐Halosuccinimides

“…So far, many synthetic methodologies for α,α‐dihaloamides are available, among which the most prevalent strategy relies heavily upon the ammonolysis of α,α‐dihalocarboxylic acid derivatives with an amine 3,5. Other methods are reported by the direct α,α‐dihalogenation of β‐oxo amides with various halogenating systems, such as chlorine/ hv ,6a SO 2 Cl 2 ,6b N ‐chlorosuccinimide/NaH,6c aqueous bromine,6d and PhI(OAc) 2 /ZnX 2 (X = Cl, Br) 6e. Nevertheless, some of these methods involve hazardous reagents, harsh reaction conditions, or generation of wastes that not only reduce process efficiency but also pose environmental problems.…”

Electrosynthesis of 3-Chloro-1,4-disubstituted-2(1H)- quinolinones and 3,3-Dichloro-4-hydroxy-1,4-disubstituted- 3,4-dihydro-2(1H)-quinolinones, as Well as a New Convenient Process to Dioxindoles

“…Some described synthetic procedures to produce 3-chloro-1,4-dialkyl-2(1 H )-quinolones involve halocarbene intermediates. , However, 3-halo- N -substituted-2(1 H )-quinolinones have been prepared by using the Vilsmaier reagent, − and 3,3-dichloro-4-aryl- N -substituted-3,4-dihydro-2(1 H )-quinolone synthesis involves cyclization of β-keto amides in H 2 SO 4 …”