- ORGANOPHOSPHORUS INTERMEDIATES XI. PREPARATION AND STEREOCHEMISTRY OF P-PHENYLATED 1,3-DIPHOSPHOLANE, 1,3- AND 1,4-DIPHOSPHORINANES, 1,4-DIPHOSPHEPANE AND 1,5-DIPHOSPHOCANE
-
The eponymous 5-, 6- and seven-membered diphosphorous heterocycles have been prepared by alkylating diphosphides with α,ω-dihalides and separated into stereoisomers.One isomer of the 1,5-diphosphocane has been obtained by reduction of the dioxide with trichlorosilane.Stereochemistry is assigned on the basis of (1)H, (13)C, (31)P nmr, infrared and mass spectral studies and X-ray structure of the trans-1,4-diphosphorinane.Thermal inversion studies on the 5-, 6- and 7-membered heterocycles are described. Key words: Heterocycles; diphosphines; stereochemistry; nmr; inversion.
- Brooks, Peter J.,Gallagher, Michael J.,Sarroff, Adrian,Bowyer, Michael
-
p. 235 - 248
(2007/10/02)
-
- PREPARATION AND STEREOCHEMISTRY OF SOME DIPHOSPHORUS HETEROCYCLES
-
Cleavage of Ph2P(CH2)nPPh2(n=2-5) with Li in THF provides a convenient sources of the corresponding dianions which may be alkylated with X(CH2)nX (X=Cl, Br, n=1-3) to give diphosphorus heterocycles with a ring size 5-7.These are separated into their stereoisomers and stereochemical assignments made.An alternative route to an eight-membered ring is described.
- Brooks, P.,Gallagher, M.J.,Sarroff, A.
-
p. 389 - 392
(2007/10/02)
-
- Synthesis and Properties of Open-Chain and Cyclic 1λ3,3λ3-Diphosphaalkanes RR'P-CH2-PR'R
-
Disecondary methylenediphosphanes R(X)PCH2P(X)R with their adjustable positive or negative polarity (X = H, Cl), which are useful building blocks for organophosphorus synthesis, were prepared by multi-step substitution of chlorine atoms in methylenebis(di
- Schmidbaur, Hubert,Schnatterer, Stefan
-
p. 2832 - 2842
(2007/10/02)
-