Rosenthal reagent

With its tetrasubstituted carbon, the zirconaaziridine 2i remains ligand-free in THF, but in the presence of PMe3 it forms a PMe3 adduct. Complex 2j [33], prepared in a similar manner with the Rosenthal reagent 8 [34], is the only zirconaaziridine with a tetrasubstituted carbon that has had its structure determined by X-ray studies. The stability of its pyridine adduct reflects the fact that pyridine is a stronger donor ligand than THF. 

Similarly, the reaction of Rosenthal reagent 1-12 with l,4-di-ferf-butyl-l,3-butadiyne gave zirconacyclopentatriene 1-13 as product of intramolecular cyclization. Zirconacyclopentatriene 1-13 have been considered as bent allene, and both zirconacyclopentyne 1-11 and zirconacyclopentyne 1-13 feature ring strain and are structurally interesting molecules (Scheme 1.10) [41]. 

Rosenthal, A.F., Gringanz, A., and Vargas, L.A., Bis(trimethylsilyl) trimethyl-siloxymethylphosphonite A useful reagent for the introduction of the hy-droxymethylphosphinate group, Chem. Commun., 384, 1976. 

Rosenthal s reagent, Cp2Zr(Me3SiCCSiMe3) (12), which can be prepared from bis(tri-methylsilyl)acetylene and either Cp2ZrCl2/Mg [18] or Cp2ZrBu2 [19], has also proved useful (Eq. 2.7). 

A. Rosenthal and S. N. Mikhailov, Branched-chain sugars. Modifications in the reaction of l,2 5,6-di-0-isopropylidene-oi-D-ribo-hexofuranos-3-ulose with Giignard and oiganolithium reagents, J. Carbohydr. Nucleosides Nucleotides 6 237 (1979). 

Rosenthal and Lee prepared examples of these C-nucleosides (310) by cyclocondensation of the 2,5-anhydro-D-allonic acid 79 with 1-hydra-zinophthalazine in the presence of a coupling reagent (CR) (78MI12) (Scheme 94). 

Recently, Rosenthal, MiiUer, and coworkers investigated the reactivity of a novel [PNPN]-Cr system toward AIR3 reagents and were able to isolate a dimeric Cr/Al heterometaUic complex that, in the presence of TEA, mediates the selective trimerization of ethylene (Fig. 12c) [181]. 

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