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In this work, we unveil a novel synthesis of bench stable Ni (II) complexes supported by tetradentate Schiff‐base ligands and the complexes were devoid of any phosphine or phosphine‐based ligand. These Ni‐complexes were successfully applied for the dehydrogenation of secondary alcohols for ketone and ketazine syntheses. Secondary alcohols with different functional groups were well tolerated during catalytic cycle. Moreover, we successfully extended this protocol for the synthesis of biologically significant ketones and ketazines. On the basis of various control experiments, probable reaction pathway was proposed, and an acceptorless alcohol dehydrogenation mechanism was suggested. [ABSTRACT FROM AUTHOR]

Herein we first report the unprecedented synthesis of tetrazene‐based cobalt complexes using unusual coupling of amines via dehydrogenation. These cobalt complexes were employed for dehydrogenative coupling reactions to synthesize N‐heterocycles (quinoline, and quinazolinone). Based on control experiments and IR identification of intermediates, we proposed a plausible reaction mechanism. Synthesis protocols were utilized for preparative scale synthesis and biologically active molecule (±)‐galipinine synthesis. [ABSTRACT FROM AUTHOR]

This work describes a new well-defined, air-stable, phosphine free palladium(II) [Pd(L)Cl] (1) catalyst. This catalyst was utilized for N-alkylation of amines and indole synthesis where H2O was found to be the by-product. A broad range of aromatic amines were alkylated using this homogeneous catalyst with a catalyst loading of 0.1 mol%. Greener aromatic and aliphatic primary alcohols were utilized and a hydrogen auto-transfer strategy via a metal–ligand cooperative approach was investigated. The precursor of the antihistamine-containing drug molecule tripelennamine was synthesized on a gram scale for large-scale applicability of the current synthetic methodology. A number of control experiments were performed to investigate the possible reaction pathway and the outcomes of these experiments indicated the azo-chromophore as a hydrogen reservoir during the catalytic cycle. [ABSTRACT FROM AUTHOR]

The article offers information on polyether ether ketone (PEEK), one of the used in dentistry especially in the branch of prosthodontics. Topics discussed include major beneficial property for orthopedics implant application, several reseaches to improve the bioactivity of PEEK implants and advantages of applying PEEK.

Hydatidiform mole is an abnormal pregnancy common in Asian populations compared to western countries; however, a partial hydatidiform mole is relatively uncommon and very challenging to diagnose on ultrasound. We reported a 24 years old female visited our clinic whose first antenatal visit was regular with normal viable fetus on ultrasonographic scan. However, an uneventful scan at 12 weeks period of gestation revealed a large irregular gestational sac with the disproportionately small embryo corresponding to 6+6 weeks with no cardiac activity. Additionally, there was markedly thickened placenta measuring 30mm in thickness without cystic spaces within the placenta. Further, her beta-human chorionic gonadotrophin level was very high and suction evacuation sample showed hydropic chorionic villi lined by trophoblastic cells with cistern formation and scalloped border. In conclusion, partial hydatidiform mole is an uncommon molar pregnancy rarely diagnose on ultrasonography. Late first-trimester scan and excessively high beta-human chorionic gonadotrophin levels confirm the diagnosis. Keywords: Hydatidiform mole; molar pregnancy; partial hydatidiform mole.