Triphenylgermyl radicals

In this reaction, the diphenylmethylgermyl radical is produced. Although its Ge HF coupling constant has not yet been measured, it may be similar to that of the triphenylgermyll radical (A/g s = 8.32 mT). Typical a values for the Ge-enrichment observed for this reaction in the absence and presence of external magnetic fields are listed in Table 9-2. The 5-dependence of this MIE of Ge is shown in Fig. 9-4(b) and can be explained by the HFCM. 

Laser photolysis of hexaphenylsilane (and hexaphenylgermane) was used to observe the TR EPR spectra of triphenylsilyl and triphenylgermyl radicals for the first time in fluid solutions. The spectra show TM and RPM CIDEP, which indicates that the homolysis of the M-M bond occurs via the triplet state. The triphenylstannyl radical was not observed. 

In a useful application, Kahne and Gupta reported the radical hydroxymethyla-tion (formylation and in situ reduction) of organic halides, including sugar derivatives, using a catalytic amount of triphenylgermyl hydride in the presence of so-... 

Radical addition of triphenylgermane to vinyl oxiranes proceeded in the presence of triethylborane to yield 4-triphenylgermyl-2-buten-l-ol derivatives in good yield. Iodo acetals, prepared by iodoetherification of vinyl ethers with the allylic alcohol, underwent radical cychzation to give 2-alkoxy-4-vinyltetrahydrofurans which were converted into 4-vinyltetrahydro-2-furanones by Jones oxidation (Scheme 11.22) [38]. 

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