Radioactive decay of Eu154

The radioactive decay of Eu¹⁵⁴ (t _1/2=16y), obtained from thermal neutron irradiations of 95% enriched Eu¹⁵³, has been studied by using the Seigbahn-Slätis intermediate image spectrometer, a thin lens magnetic spectrometer and a coincidence scintillation spectrometer. The following gamma-rays (energy in kev.) have been identified as belonging to this isotope: 123, 248, 585, 717, 759, 875, 998, 1007, 1285, 1600. Beta end points of Eu¹⁵⁴ were measured at 275 (20%), 590 (45%), 890 (23%) and 1860 (12%). The K-conversion coefficient of 123 kev. gamma-ray has been experimentally determined to be ～0·5. On the basis of gamma-gamma and beta-gamma coincidences, the decay scheme of Eu¹⁵⁴ has been deduced: the resulting level-structure of Gd¹⁵⁴ conforms well with the predictions of the unified nuclear model.     

Clay Supported Bis-(trimethylsilyl)-chromate: An Efficient Reagent for Oxidative Deoximation

Summary.  A convenient method for the direct conversion of oximes to carbonyl compounds upon treatment with clay supported BTSC under classical heating as well as microwave irradiation in a solvent-free system is described.     

Heteroannulation Through Palladium Catalysis: A Novel Cyclization Leading to Regioselective Synthesis of 3-Substituted Thiazolo[3,2-c]1,2,4-triazin-5-ones

A convenient, general, and one-pot synthesis of substituted thiazolo[2,3-c]1,2,4-triazinone from 3-propargylmercapto-1,2,4-triazin-5-one and aromatic iodide via palladium catalysis is described.     

New Synthesis of 3-Alkyl Coumarins

3-Alkyl coumarins are reported to have anthelmintic, hypnotic and insecticidal properties^1–3. Here we report a novel general method for the synthesis of 3-alkylated coumarins. This involves direct C-alkylatioa at the C-3 position of 3-carbethoxy-3,4-dihydrocoumarin followed by hydrolysis, decarboxylation and dehydrogenation of the resulting dihydrocoumarin. 3-Methyl-, 3-ethyl-, 3-n-pro-pyl-, and 3-benzylcoumarins have been synthesised in good yields following the same procedure depicted in the Scheme-1.     

Asymmetric synthesis of a dopamine D1 agonist,dihydrexidine from d-serine

A scalable asymmetric synthesis of trans-2-amino-6,7-dimethoxy-1-phenyltetralin 2 and its N-nosyl derivative 12 have been achieved from Garner aldehyde derived from easily available d-serine using a stereoselective PhMgBr addition, Wittig reaction and TFA-mediated Friedel–Crafts cyclization as the key steps. The synthesis of dihydrexidine is accomplished from the N-nosyl-2-amino-1-phenyltetralin 12.