Synthesis and thermal behavior of some diisocyanate–silane compounds

Some silica-organic compounds were prepared by an addition reaction between γ-amino-propyl-triethoxy silane and 4,4′-diphenylmethane diisocyanate. The obtained products were characterized by FTIR spectrometry. The essential synthesis parameter was the molar ratio between the two reactants. The thermal behavior of the products was rather good, until 150 °C no mass loss or thermal effects being observed. The thermal behavior was determined under non-isothermal conditions, using TG/DTG/HF diagrams. Due to the hydroxyl end-groups, these compounds are recommended for adhesives between organic and inorganic surfaces.     

An Ethylene‐Bridged Phosphane/Borane Frustrated Lewis Pair Featuring the ‐B(Fxyl)2 Lewis Acid Component

Hydroboration of dimesitylvinylphosphane with bis[3,5‐bis(trifluoromethyl)phenyl]borane [HB(Fxyl)₂] gave the intramolecular ethylene‐bridged P/B frustrated Lewis pair (FLP) Mes₂PCH₂CH₂B(Fxyl)₂. The new compound underwent a variety of typical FLP reactions such as P/B‐addition to the carbonyl group of p‐chloro‐benzaldehyde. Cooperative N,N‐addition to nitric oxide gave the respective persistent P/B FLPNO^. radical, which readily reacted with 1,4‐cyclohexadiene by H‐atom abstraction to yield the corresponding P/B FLPNOH product. The B(Fxyl)₂‐containing FLP reacted as a template for the HB(C₆F₅)₂ reduction of carbon monoxide to the formyl stage to give the respective FLP(η²‐formylborane) product. Most products were characterized by single‐crystal X‐ray crystal structure analysis.