No abstract

The synthesis of diversely substituted 1,3,5-substituted pyrazoles from the reaction of acetylenic ketones with substituted hydrazines is reported. The reactions were shown to be highly regioselective regardless of the nature of the substituents in the substrates and afforded essentially single pyrazole isomers in excellent yields.

[structure: see text]. The NK-1 receptor antagonist 1 has been prepared in seven steps from phenylglycine methyl ester. The key steps are a double ring closing metathesis reaction of tetraene 7 to prepare spirocycle 6 and a reductive Heck reaction to introduce the aryl moiety. This latter reaction discriminates the olefins of compound 6 and proceeds in a highly regio- and stereoselective manner.

The structures of the microcladallenes A, B, and C have been established from spectroscopic data and X-ray crysta I I og ra p h ic an a I ysis of m icrocl a d a I I e n e B.

The crystal structure of CsMnBr3, determined from Weissenberg data, is hexagonal with a=7-609 (15), c=6.52 (5) A and Z=2. Cs, Mn and Br atoms are located at the special positions 2(d), 2(a) and 6(h), respectively, of the space group P63/mmc, the structure being isomorphous with that of CsNiCI3.