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Nanoplatelets of the title compound are prepared by hydrothermal reaction of an aqueous NaOH solution of SnCl2 (pH 13, autoclave, 180 °C, 16 h).

The efficient, simple method gives an access to some previously unknown compounds avoiding the use of low-boiling, gaseous reagents.

The Ruppert—Prakash reagent Me3Si—CF3 is an efficient source of difluorocarbene which is generated by sodium iodide or tetrabutylammonium difluorotriphenylsilicate as the initiator.

The reaction proceeds in water without any additives and requires addition of the fresh catalyst after completion of the reaction and another heating under microwave conditions to overcome deactivation and to obtain higher conversion.

5-Fluorouridine (FUrd) has been successfully converted to 5'-O-(4,4'-dimethoxytrityl)-2'-O-(tertbutyldimethylsilyl)-5-fluorouridine 3'-(cyanoethyl N,N-diisopropyl(phosphoramidite) by methods similar to those employed for the preparation of other ribonucleoside phosphoramidites. The desired product, as well as its precursors and the incorrect regioisomers, are prepared and fully characterized by 1 H NMR, 19 F NMR, 31 P NMR, FAB-MS, UV absorbance, elemental analysis, and melting points. The purified material is used for the production of RNA by solid-phase methods. Coupling yields of 94% are obtained with this material. The resulting RNA is readily purified and used for biophysical studies. The self-complemetary RNA decamer 5'-rGCGAAU(FU)CGC is prepared and purified. The material adopts an A-form duplex in solution at neutral pH as characterized by CD spectroscopy. The thermal stability of the duplex is similar to the parent duplex oligoribonucleotide prepared with uridine instead of 5-fluorouridine. The control duplex has a T m of 53.8 and the FUrd substituted duplex has a T m of 56.6 ×b0° C as determined by UV hyperchromicity at 260nm. The CD spectra and UV hyperchromicity data for the duplex oligoribonucleotide containing FUrd have a slight pH dependence indicating that ionization of FUrd has a slight but measurable impact on RNA duplex stability. 1D NMR spectroscopy of the imino hydrogens for this duplex in H 2 O solution confirms the formation of Watson-Crick base pairs. The imino hydrogen resonance for the FUrd-A base pair is moved downfield and broadened compared with a control duplex oligoribonucleotide as a consequence of the electron-withdrawing inductive effect of fluorine