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Condensation of 8-arylidenehexahydroquinazoline-2-thiones with di- and trihydroxybenzenes affords the new heterocyclic system, viz., octahydrochromeno[3,2-i]quinazoline-2(1H)-thiones, in which the substituents in both the chromane and quinazoline rings can be varied over a wide range.

There is a significant specific geminal interaction of the oxygen and chlorine atom in aryl chloromethyl ethers, p-RC6H4OCH2Cl, although this effect is less than in alkyl chloro-methyl ethers.

Diethylacetyl phosphite và diethyl chlorophosphite phản ứng với biacetyl, tạo thành các 1,3,2-dioxaphospholene với nguyên tử photpho ngũ phối, như các dẫn xuất khác của axit photphoric. Các hợp chất này nhanh chóng biến đổi thành các dẫn xuất không vòng hoặc vòng của photpho tứ phối.

The reactions of cluster (μ-H)Os3(CO)10(μ-OH) with ethyl and isopropyl esters ofl-oxyproline were studied. In the presence of Me3NO intermediate complex (μ-H)Os3(CO)9(μ-OH)L (L — isopropyl ester ofl-oxyproline) is formed, which slowly converts to the more stable cluster (μ-H)Os3(CO)9 $$\left\{ {\mu ,\eta ^2 } \right.--{\rm O}|\overline {CHCH_2 CH(COOPr^i )NH} \mathop C\limits^| \left. {H_2 } \right\}$$ . Cluster complexes containing chelate-bridging heterocycles were also obtained by heating (μ-H)Os3(CO)10(μ-OH) with esters ofl-oxyproline. In both cases, only one of the possible diastereomeric complexes (μ-H)Os3(CO)9 $$\left\{ {\mu ,\eta ^2 } \right.--{\rm O}|\overline {CHCH_2 CH(COOPr^i )NH} \mathop C\limits^| \left. {H_2 } \right\}$$ (R = Et, Pri) is formed, which indicates that the reactions are stereospecific. Based on analysis of Dreiding's models, an attempt to determine the absolute configuration of the obtained clusters was made.

A theory of the Jahn-Teller effect in trinuclear CrIII and FeIII μ-oxocomplexes based on the generalized angular overlap model is developed. The central bridging O atom is not localized at the center of the triangle formed by the metal atoms. Rather, it executes a free or hindered motion along a circular groove of radius 0.05–0.1 Å. The theory provides a qualitative explanation for apparent discrepancy between the X-ray structural data and the results of the heat capacity, magnetic susceptibility, and inelastic neutron scattering measurements. Namely, X-ray structural data correspond to a regular triangle symmetry while other data correspond to an equilateral or even irregular triangle symmetry.