In:
Zeitschrift für Naturforschung B, Walter de Gruyter GmbH, Vol. 57, No. 9 ( 2002-9-1), p. 1027-1035
Abstract:
The reaction of PCl 3 at r. t. with an equimolar amount of NaR* in heptane gives the colorless phosphane R*PCl 2 (1), the colorless diphosphane R*ClP-PClR* (2), the light green diphosphene R*P=PR* (4), the cyclotetraphosphane R* 2 P 4 Cl 2 (6) (not isolated), the light yellow bis(cyclotriphosphanyl) P 6 R* 4 (7), the cyclotriphosphane R* 2 P 3 Cl (8) (not isolated), and the colorless bicyclophosphane P 4 R* 2 (9).With a threefold molar amount of NaR* in tetrahydrofuran the blue violet triphosphanide NaP 3 R* 2 (10), the dark red tetraphosphanide NaP 4 R* 3 (11), and the orange pentaphosphanediide Na 2 P 5 R* 3 (12) are formed from PCl 3 besides the phosphanides NaPR* 2 , Na 2 PR* (isolated), NaP 2 R* 3 and Na 2 P 2 R* 2 . With a four-fold molar amount of KR* in benzene PCl 3 gives the green diphosphanediide K 2 P 2 R* 2 and the red phosphanediide K 2 PR*, and with an equimolar amount of ZnR* 2 in heptane the compounds 1, 2, 4, 7 and 8 are obtained. The compound R*P=PR* (4), the first diphosphene with two silyl substituents, is formed in high yields from the action of Na on R*PCl 2 in heptane at 90 "C. It gives a [2+4] cycloadduct with 2,3-dimethylbutadiene and phosphanides (Na 2 P 2 R* 2 or Na 2 PR*) with Na or NaR*. Bicyclotetraphosphane P 4 R* 2 (9) (structure: two R*P 3 rings with a common edge) is exclusively obtained from Na 2 P 4 R* 2 (formed quantitatively from P 4 and 2 NaR*) and TCNE. 9 may be reduced (Na, THF) with reformation of Na 2 P 4 R* 2 and reacts in the presence of NaR* with formation of dark red NaP 4 R* 3 (11) (structure: P 3 ring with two R* substituents in trans position and one PNaR* substituent). Straightforward syntheses of halogenophosphanes include (i) reactions of ZnR* 2 with PCl 3 or PBr 3 (mole ratio 1 : 2) in heptane to form R*PCl 2 (1) or R*PBr 2 , and (ii) reaction of R* 2 with R*PCl 2 (mole ratio 1 : 2) without a solvent, or of KR* and PCl 3 (mole ratio 2 : 1) in benzene to formR*ClP-PClR* (2). The halogenophosphanes R* 2 P 3 Cl (8) (structure: P 3 ring with two R* substituents in trans position and one Cl substituent) as well as R*2P 4 Cl 2 (6) (structure: P 4 ring with alternating R* and Cl substituents) have not been isolated. The 31 P-NMR spectra and the pathways of formation of the phosphorus compounds are discussed
Type of Medium:
Online Resource
ISSN:
1865-7117
,
0932-0776
DOI:
10.1515/znb-2002-0909
Language:
English
Publisher:
Walter de Gruyter GmbH
Publication Date:
2002
detail.hit.zdb_id:
2078109-X
detail.hit.zdb_id:
124635-5
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