ChemInform Abstract: Synthesis of Pyrimidine‐Fused Benzazepines from 5‐Allyl‐4,6‐dichloropyrimidines.

Quintero, Lina M. Acosta; Jurado, Jorge; Nogueras, Manuel; Palma, Alirio; Cobo, Justo

doi:10.1002/chin.201551169

Cited by 1 publication

(1 citation statement)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We have previously described a versatile two-step synthetic approach to the stereoselective synthesis of biologically active 2-substituted(alkenylaryl/heteroaryl)-4-hydroxytetrahydro-1benzazepines starting from simple and synthetically readily available N-substituted 2-allylanilines (Gó mez- Ayala et al, 2006Ayala et al, , 2010Acosta et al, 2010;Acosta-Quintero et al, 2012;Blanco et al, 2014).…”

Section: Introductionmentioning

confidence: 99%

A concise and versatile route to tetrahydro-1-benzazepines carrying [a]-fused heterocyclic units: synthetic sequence and spectroscopic characterization, and the molecular and supramolecular structures of one intermediate and two products

et al. 2019

Self Cite

View full text Add to dashboard Cite

A concise, efficient and versatile route from simple starting materials to tricyclic tetrahydro‐1‐benzazepines carrying [a]‐fused heterocyclic units is reported. Thus, the easily accessible methyl 2‐[(2‐allyl‐4‐chlorophenyl)amino]acetate, (I), was converted, via (2RS,4SR)‐7‐chloro‐2,3,4,5‐tetrahydro‐1,4‐epoxy‐1‐benzo[b]azepine‐2‐carboxylate, (II), to the key intermediate methyl (2RS,4SR)‐7‐chloro‐4‐hydroxy‐2,3,4,5‐tetrahydro‐1H‐benzo[b]azepine‐2‐carboxylate, (III). Chloroacetylation of (III) provided the two regioisomers methyl (2RS,4SR)‐7‐chloro‐1‐(2‐chloroacetyl)‐4‐hydroxy‐2,3,4,5‐tetrahydro‐1H‐benzo[b]azepine‐2‐carboxylate, (IVa), and methyl (2RS,4SR)‐7‐chloro‐4‐(2‐chloroacetoxy)‐2,3,4,5‐tetrahydro‐1H‐benzo[b]azepine‐2‐carboxylate, C14H15Cl2NO4, (IVb), as the major and minor products, respectively, and further reaction of (IVa) with aminoethanol gave the tricyclic target compound (4aRS,6SR)‐9‐chloro‐6‐hydroxy‐3‐(2‐hydroxyethyl)‐2,3,4a,5,6,7‐hexahydrobenzo[f]pyrazino[1,2‐a]azepine‐1,4‐dione, C15H17ClN2O4, (V). Reaction of ester (III) with hydrazine hydrate gave the corresponding carbohydrazide (VI), which, with trimethoxymethane, gave a second tricyclic target product, (4aRS,6SR)‐9‐chloro‐6‐hydroxy‐4a,5,6,7‐tetrahydrobenzo[f][1,2,4]triazino[4,5‐a]azepin‐4(3H)‐one, C12H12ClN3O2, (VII). Full spectroscopic characterization (IR, 1H and 13C NMR, and mass spectrometry) is reported for each of compounds (I)–(III), (IVa), (IVb) and (V)–(VII), along with the molecular and supramolecular structures of (IVb), (V) and (VII). In each of (IVb), (V) and (VII), the azepine ring adopts a chair conformation and the six‐membered heterocyclic rings in (V) and (VII) adopt approximate boat forms. The molecules in (IVb), (V) and (VII) are linked, in each case, into complex hydrogen‐bonded sheets, but these sheets all contain a different range of hydrogen‐bond types: N—H…O, C—H…O, C—H…N and C—H…π(arene) in (IVb), multiple C—H…O hydrogen bonds in (V), and N—H…N, O—H…O, C—H…N, C—H…O and C—H…π(arene) in (VII).

show abstract

Section: Introductionmentioning

confidence: 99%