Three tetrahydroisoquinolinedione derivatives

N‐(2‐Chloro­benzyl)‐1,2,3,4‐tetra­hydro­iso­quinoline‐1,3‐dione, C₁₆H₁₂ClNO₂, crystallizes in P2₁/n with three crystallographically independent mol­ecules in the asymmetric unit, which differ slightly in conformation, N‐(2‐bromo‐4‐methyl­phenyl)‐1,2,3,4‐tetra­hydro­iso­quinoline‐1,3‐dione, C₁₆H₁₂BrNO₂, crystallizes in P2₁/n with one mol­ecule in the asymmetric unit andN‐(2,3‐di­chloro­phenyl)‐1,2,3,4‐tetra­hydro­iso­quinoline‐1,3‐dione, C₁₅H₉Cl₂NO₂, crystallizes in P2₁/c with one mol­ecule in the asymmetric unit. In all three structures, the heterocyclic rings adopt approximately planar conformations. The pyridine rings are orthogonal to the substituted phenyl rings. In all three structures, the crystal packing is stabilized by intermolecular C—H?O hydrogen bonds.     

An approach towards the oxidation of 2-amino-4H-chromenes to 2-imino-2H-chromenes

A novel method for the synthesis of 2-imino-2H-benzo[h]chromenes via the sequential addition of N-chlorosuccinimide and triethylamine to 2-amino-4H-benzo[h]chromenes has been established. This reaction protocol represents an efficient synthetic strategy to form iminochromene derivatives under mild reaction conditions, which utilizes readily accessible aminochromenes as starting materials and tolerates a wide range of substrates.     

Crystal structure of 8-(3,4-dimethylphenoxy)-16H dinaphtho[2,1-d:1′,2′-g] dioxaphosphocin 8-oxide

The title compound, C₂₉H₂₃O₄P crystallizes in the triclinic space group witha=9.636(1),b=10.327(1),c=13.406(1) Å, =102.22(1), =100.59(1), =109.84(1)^o.V=1178.1(2) ų,Z=2,D _cal=1.32 M gm^–3, (CuK)=6.16 cm^–1, (CuK)=1.5418 Å andT=295K. The structure was solved by direct methods and refined by full-matrix least-squares method to a finalR=0.052 andwR=0.063 for 2708 reflections withl3(l). The napthalene ring A lies perpendicular to the best plane of the phenyl ring [91.6(1)^o] and the ring B orients at an angle of 55.7(1)^o with this plane and is inclined at an angle of 77.8(1)^o with ring A. The heterocyclic phosphorous eight-membered ring assumes a distorted boat conformation.DCB Contribution No. 822.     

Crystal structure analysis of 5‐amino‐7‐(pyrrolidin‐1‐yl)‐2,4,4‐trimethyl‐1,4‐dihydro‐1,6‐naphthyridine‐8‐carbonitrile

The title compound [CCDC 199359], C₁₆H₂₀N₅ crystallized in Monoclinic system with the space group C2/c. The unit cell parameters are: a = 16.554(6), b = 12.145(4), c = 16.221(5)Å and β = 102.67(1)°. The molecular structure is stabilized by an intramolecular C‐H…N type hydrogen bond and the molecular packing by the intermolecular C‐H…N and N‐H…N type hydrogen bonds. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)