Methoden zur Synthese von Alkyl‐und Arylbis (Trimethylsilyl)‐sowie Alkyl‐und Aryltrimethylsilylphosphanen werden beschrieben. Die zur Darstellung der Titelverbindungen benötigten primären Phosphane wurden nach bekannten Methoden (Reduktion mit LiAlH4) synthetisiert. Alkyl‐ und Arylbis(trimethylsilyl)phosphane sind aus den entsprechenden Dilithiumphosphiden (Primäres Phosphan und Methyllithium) und Trimethylchlorsilan oder aus Lithiumbis (trimethylsily) phosphid und Alkylhalogeniden zugänglich. Geeignete Synthesen für Alkyl‐und Aryltrimethylsilyphosphane sind die Umsetzungen der Alkyl‐und Aryllithiumphosphide mit Trimethylchlorsilan (Ausnahme; Methyl) sowie der Alkyl‐ und Arylbis (Trimethylsilyl) phosphane mit Methanol. Die Reaktion zwischen Phenylbis (trimethylsilyl)‐Phosphan und wasser wurde naher untersucht und die Bildung von Trimethylsilanol 1H‐NMR‐ spektroskopisch nachgewiesen. Lithiumtrimethylsilylphosphide reagieren mit 2, 2‐Dimethylpropionylchlorid zu den (2,2‐Dimethylplropionyl) trimethylsilyphosphanen (Ketoformen).

There is a multitude of chemical and biochemical detection methods for sugars. Which ones would be most practical in an undergraduate laboratory setting? How to best detect non-reducing disaccharides? How to make such lab fun for students to perform? After trying several spectrophotometric methods, it was found that chemical detection by dinitrosalicylic acid and biochemical detection by hexokinase/glucose-6-phosphate dehydrogenase reagent are most appropriate. Sucrose, a non-reducing disaccharide was digested chemically with hydrochloric acid and biochemically with invertase. It was concluded that chemical detection and biochemical detection compliment each other. Chemical digestion method was preferred over the digestion by invertase. These methods were applied for testing the validity of sugar ingredients printed on drink labels as well as the measurement of sugar levels in ripening bananas at two different conditions. The comprehensive comparison of these methods and the detection of sugar concentrations in interesting samples might serve as a basis for an undergraduate chemistry laboratory.

Tetraaza‐λ31‐diphospha‐stanna‐bicyclo[3.1.1]heptanes: Reactive Precursors of New Heterobicycles 2,4,6,7‐Tetraaza‐1λ3,5λ31‐diphospha‐3‐stannabicyclo[3.1.1]heptane (4) is obtained by stannazane cleavage of the diazadistannetidine (Me2SnNtBu)2 (2) with the diazadiphosphetidine (CIPNtBu)2 (1). A chloro derivative of 4, compound 8, is formed by substitution of one methyl group attached to the tin atom in 4 against chlorine in a 1:1 reaction with PhBCl2, while additional PhBCl2 leads to an exchange of the MeClSn against the PhB group to give 9. Oxidation of both phosphorus atoms of compound 4 with sulfur leads to 7. An unexpected introduction of a diphenyldiphosphane unit with formation of 11 proceeds by stannazane cleavage of 4 with PhPCl2. The structures of the bicyclic products 4, 7, 8, and 11 are ascertained by detailed NMR studies, particularly by means of 15N‐NMR spectra, and by X‐ray structure determinations. All heterobicycles contain a planar diazadiphosphetidine unit. The ring system 8 features an additional Sn – N bond due to transannular interaction of the tin atom with one of the nitrogen atoms of the four‐membered P2N2 ring fragment. The PP bond distance in 11 with 2.175 Å is one of the shortest found in heterocycles containing P2 units.

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