Process for the preparation of a dendritic macromolecule

The invention relates to a process for the preparation of a dendritic macromolecule, wherein an amount of a core molecule comprising at least one functional group is dissolved in a solvent, after which alternatingly an addition reaction and a hydrogenation reaction are carried out, during the addition reaction vinyl cyanide units being added to the solution which react with the functional groups in such a manner that a dendritic macromolecule with terminal cyanide groups is formed, and during the hydrogenation reaction the cyanide groups being reduced in solution by means of hydrogen and a suitable catalyst in such a manner that functional amine groups are formed, wherein the solvent in which the hydrogenation reaction takes place is an alcohol which contains an amount of ammonia, the molar ratio between the amount of ammonia and the number of cyanide groups being higher than 0.8

Dendritic macromolecule and the preparation thereof

The invention relates to a dendritic macromolecule comprising a core and branches emanating from the core wherein the branches are based on vinyl cyanide and/or fumaryl dinatrile units. The invention also relates to processes for preparing these dendritic macromolecules. The dendritic macromolecules according to the invention are not sensitive to degradation through hydrolysis reactions and are also very stable at a high temperature. The processes are very suitable for large scale production of the dendritic macromolecules without requiring purification of reaction intermediates

Protonation as a driving force for pentacoordination of phosphorus

CNDO/2 calculations are reported on four caged phosphorus compounds, Y-P(OCH2CH2)3X (X = N, CH; Y = O, OH+, H+). Structures with and without a transannular bond between P and X were taken into account; the influence of this bond on the stability of the compounds was examined. For X = N and Y = H+ the lowest-energy structure corresponds with the geometry found by X-ray analysis. If X = CH, formation of a transannular bond proves to be unlikely, as expected. The calculations predict the formation of a P-N bond upon protonation of the phosphate (X = N, Y = O). The net atomic charges in the protonated phosphite were used to calculate its NMR coupling constant, 1JPH, which correlates well with the value found experimentally

Group transfer reactions via pentavalent phosphorus intermediates

No abstract