Rearrangements of 2-Furfurylidenes − Synthesis of Acylsilanes and Acylstannanes

Abstract

The 2‐furfuryldiazomethanes 3c and 3d, with trimethylsilyl and trimethylstannyl groups, respectively, in the 5‐position, were generated from the sodium salts of the corresponding tosylhydrazones and matrix‐isolated in argon at 10 K. Photolysis of the diazo compounds 3 resulted in the formation of the highly unsaturated acylsilanes and acylstannanes 2 in clean reactions. Comparison of the experimentally obtained IR spectra with those obtained from DFT calculations revealed that compounds 2 were formed in their thermodynamically less favorable (Z) conformations.

Insertion of an Isolable Dialkylstannylene into C–Cl Bonds of Acyl Chlorides Giving Acyl(chloro)stannanes

“…More recently, an isolable silenyllithium was synthesized using an acyl­(halo)­silane . On the contrary, less attention has been focused on the corresponding acylstannanes, despite their great potential in synthetic organic chemistry. Acylstannanes have often been synthesized using the reactions of acyl chlorides (or carboxylic acid esters and thioesters) with stannyl­lithiums , and those with hexa­methyl­distannane in the presence of palladium catalysts (eqs and 2), and using some other specific reactions such as photolysis of stannylfuranes .…”