Palladium nanoparticle-decorated reduced graphene oxide sheets synthesized using Ficus carica fruit extract: A catalyst for Suzuki cross-coupling reactions.

We present a biogenic method for the synthesis of palladium nanoparticle (PdNP)-modified by reducing graphene oxide sheets (rGO) in a one-pot strategy using Ficus carica fruit juice as the reducing agent. The synthesized material was well characterized by morphological and structural analyses, including, Ultraviolet-Visible spectroscopy (UV-Vis), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and Transmission Electron Microscopy (TEM) and Raman spectroscopy. The results revealed that the PdNP modified GO are spherical in shape and estimated to be a dimension of ~0.16 nm. The PdNP/graphene exhibits a great catalytic activity in Suzuki cross-coupling reactions for the synthesis of biaryl compounds with various substrates under both aqueous and aerobic conditions. The catalyst can be recovered easily and is suitable for repeated use because it retains its original catalytic activity. The PdNP/rGO catalyst synthesized by an eco-friendly protocol was used for the Suzuki coupling reactions. The method offers a mild and effective substitute to the existing methods and may significantly contribute to green chemistry.

Methyl 1-ethyl-3'-[hy-droxy(naphthalen-1-yl)meth-yl]-1'-methyl-2-oxo-spiro-[indo-line-3,2'-pyrrolidine]-3'-carboxyl-ate.

In the title compound, C27H28N2O4, the pyrrolidine ring adopts a twist conformation. The plane of the indole ring is almost perpendicular to that of the pyrrolidine ring, making a dihedral angle of 88.50 (6)°. The planes of the naphthyl ring system and the pyrrolidine ring are tilted by an angle of 55.86 (5)°. The mol-ecular conformation is stabilized by intra-molecular O-H⋯O and O-H⋯N hydrogen bonds.

Methyl 9-hy-droxy-15-methyl-2-oxo-11-(pyren-1-yl)-10-oxa-15-aza-tetra-cyclo-[7.6.0.0(1,12).0(3,8)]penta-deca-3(8),4,6-triene-12-carboxyl-ate.

In the title compound, C32H25NO5, the furan and pyrrole rings each adopt an envelope conformation, the respective flap atoms being the C atom bearing the pyrene substituent and the CH2 atom adjacent to the N atom. The mol-ecular conformation is stabilized by an intra-molecular O-H⋯N hydrogen bond. In the crystal, C-H⋯O contacts link the mol-ecules, forming a two-dimensional network parallel to (001).

Methyl 8-bromo-3-[1-(4-meth-oxy-phen-yl)-4-oxo-3-phenyl-azetidin-2-yl]-1-methyl-1,2,3,3a,4,9b-hexa-hydro-chromeno[4,3-b]pyrrole-3a-carboxyl-ate.

In the title compound, C30H29BrN2O5, the ß-lactam ring is essentially planar, with the O atom displaced from this plane by 0.856 (9) Å, and forming dihedral angles of 24.35 (13) and 89.42 (14)° with the planes of the benzene substituent groups on this ring. The tetra-hydro-pyran ring adopts an envelope conformation with the C atom bearing the ß-lactam ring as the flap. In the crystal, weak C-H⋯O hydrogen bonds with carboxyl and tetra-hydro-pyran O-atom acceptors give rise to a chain structure extending along the b-axis direction.