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The dicarbadodecaborate(14) dianions react with benzal-dehyde giving benzyloxydianions. The latter can be oxidized to 3- and 4-benzyloxy-o-carboranes. The cleavage of 3- and 4-benzyloxy-o-carboranes yields 3- and 4-hydroxy-o-carboranes, respectively.

The gas phase isomerization of 3-substituted o-carboranes in vacuo at 550–600° gives approximately equal quantities of 2- and 4-substituted m-carboranes. The rearrangement is of general character and may be used for the synthesis of 2- and 4-substituted m-carboranes with B[sbnd]O and B[sbnd]C bonds. 2- and 4-hydroxy-, 2- and 4-methoxy- and 2- and 4-cyano-m-carboranes were prepared by isomerization of 3-hydroxy-, 3-methoxy- and 3-cyano-o-carboranes, respectively.

Dicarbadodecaborate(14) dianions interact with aryl magnesium halides and aryl lithiums forming B-aryldianions of dicarbadodecaborate(14), the oxidation of which with CuCl2 yields 3-, 4-, 8- and 9-aryl-o-carboranes. Molecular structures of 1,2-dimethyl-9-aryl-o-carborane and 4-(p-tolyl)-o-carborane were determined. On the basis of the ionization constants of B-(p- and m-carboxyphenyl)-o-carboranes and of 19F chemical shifts in the NMR spectra of B-(p- and m-fluorophenyl)-o-carboranes, it is established that 4-o- and 9-o-carboranyl groups are electron-releasing substituents.

1. Some B-aryl-o-carboranes, containing an aryl group in the 4- and 9-positions of the o-carborane nucleus, were obtained for the first time. 2. The 4-o- and 9-o-carboranyl groups are electron-donor substituents according to the induction mechanism.

In contrast to aminoboranes that contain a tricoordination boron atom, 9-amino-m-carboranes exhibit a reactivity that is close to that of aliphatic and aromatic amines: They are smoothly acylated, alkylated, form substituted ureas with phenyl isocyanate and Schiff bases with aldehydes, and enter into the carbylamine reaction.

The results of measuring the equilibrium CH acidity of boron-substituted carboranes-12 by the transmetalation method in 1,2-dimethoxyethane show that the effect of the substituent on the methine group of carboranes is transmitted predominantly by the induction mechanism.

1. The isomerization of the 3-ethynyl- and 3-vinyl-o-carboranes in the gas phase leads to the respective formation of mixtures of the 2- and 4-ethynyl-m-carboranes and the 2- vinyl-m-carboranes. 2. The B-alkenyl-o- and B-alkenyl-m-carboranes enter into the electrophilic addition reaction more easily than the 1-alkenyl-o- and 1-alkenyl-m-carboranes.

In contrast to aminoboranes that contain a tricoordination boron atom, 9-amino-m-carboranes exhibit a reactivity that is close to that of aliphatic and aromatic amines: They are smoothly acylated, alkylated, form substituted ureas with phenyl isocyanate and Schiff bases with aldehydes, and enter into the carbylamine reaction.

Die 3-Cyan 3-Hydroxy- und 3-Methoxy-o-carborane (I) isomerisieren sich beim Erhitzen auf 550 - 600°C im geschlossenen Quarzrohr zu den m-Isomeren (II) und (III), die in etwa gleichen Mengen gebildet werden.

Durch Umsetzung von 1,2 :3,4-Di-O-cyclohexyliden-sn-myoinosit (I) mit einem Uberschus von Diphenylchlorphosphat in Pyridin und Hydrierung des Phosphorylierungsproduktes (II) an Adams-Pt wird das (+)-Diphosphat (III) (Isolierung als Cyclohexylammoniumsalz) dargestellt.

A preparative method was proposed for obtaining dihydromorphinones based on the O-demethylation of dihydrocodeinones using the AlCl3·Me2S complex in CH2Cl2.

Aus o-Carboran (I) wird das Dicarbadodecaborat( l4)dianion dargestellt, das mit Benzaldehyd zu Benzyloxydianionen reagiert.

A preparative method was proposed for obtaining dihydromorphinones based on the O-demethylation of dihydrocodeinones using the AlCl3·Me2S complex in CH2Cl2.