A Stereospecific Route to trans- and cis-1,2-Vinylenebis(diphenylphosphine)

Abstract

5 ) P S. Skell and I . Starer, J . A m . ChPm. S o r . , 84, 3962 (IR62). (6) W . F Hawthorne, UT. D . E m m o n s , and K . S RIcCallum, rbid , 8 0 , (7) J . 11. Roberts and M. H a i m a n n , i b i d . , 71, 6759 (10.53). 6393 (1958).

Th(IV) complexes with cis-ethylenebis(diphenylphosphine oxide): X-ray structures and NMR solution studies

“…The organic ligand involved in this study, cis-ethylenebis(diphenylphosphine oxide) (1), was prepared following standard procedures with stoichiometric oxidation of the starting phosphine using hydrogen peroxide (Scheme 1). The synthesis, IR and 1 H NMR characterization of this compound was reported by Daigle and co-workers, [14] and its x-ray crystal structure determined by Omondi et al [23] In our hands, we noticed a small amount of trans-isomer as a byproduct from the oxidation reaction. The desired cis-isomer 1 was readily purified, however, by recrystallization from hot benzene to give the product as a white powder in good yield.…”

“…For the preparation of ligand 1, a slightly modified procedure of that described by Daigle and coworkers [14] was followed, and the 31 P NMR data from Gallagher et al was used to confirm the stereochemistry of the alkene in the final product. [15] cis-ethylenebis(diphenylphosphine) (0.250 g, 0.631 mmol) was dissolved in tetrahydrofuran (2.50 mL) at 290 K. To this solution, 30% H2O2 (0.25 mL) was added drop wise with stirring over 5 minutes while keeping the solution chilled in an ice bath under an inert atmosphere of nitrogen gas.…”

“…These new structures have similar unit cell dimensions to structure 2, however the unit cell volumes vary slightly from 4321. (12) O10-Th1-O11 48.68 (14) As part of these experiments a crystal was also isolated with two different Th(IV)-ligand complexes in the asymmetric unit (structure 8, Figure 8). This structure was solved in the triclinic space group P-1.…”

The Synthesis of Tertiary and Secondary Phosphines and Their Applications in Organic Synthesis

“…Lithium diphenylphosphide was used in the synthesis of vinyl ditertiary phosphine [69]. In this example, a phenyl group was cleaved from triphenylphosphine using lithium metal, to give the lithiated diphenylphosphine.…”

Synthesis of Symmetrical Bis-(2-chloro-1,3,2-benzodiazaphosphorinones) Hydrolysis and Fluorination of Selected Compounds

“…It is of interest to introduce a spacer, an ali-phatic or an aromatic unit between two skeletons of type I in order to prepare the corresponding bis-PCl species with two chemically equivalent phosphorus atoms. These are extremely useful synthetic reagents for the preparation of bidentate ligands [7,8], which are widely used in coordination chemistry [9,10]. With two active P±Cl groups in one molecule, these bis-PCl derivatives may be also used as potential components of cyclocondensations in the synthesis of phosphoruscontaining macrocycles [11].…”