Efficient pyrimidine N-1-alkylation via activation of electron rich olefins with oxoammonium salts: synthesis of methoxy TEMPO substituted pyrimidine nucleoside analogs.

Our work outlines the use of oxoammonium salts in a formal 1,2 addition process to olefins giving nucleoside analogs as products. Specifically, oxoammonium salts can be added to a solution of olefin and silylated heterocycle to give Methoxy TEMPO substituted nucleoside analogs after hydrolytic workup and chromatographic purification.

Flow pattern dynamics in convecting liquid helium.

We present experimental data which correlate thermal measurements and flow visualization in convecting liquid 4He. For a small range R(C)R1, generating thermal oscillations as in earlier reports.