ChemInform Abstract: HIGHLY FLUORINATED PHOSPHORUS YLIDES AND PHOSPHONIUM SALTS

1982 ◽  
Vol 13 (8) ◽  
Author(s):  
H. SCHMIDBAUR ◽  
C. E. ZYBILL
2014 ◽  
Vol 68 (5) ◽  
Author(s):  
Seyyed Sabounchei ◽  
Mohammad Panahimehr ◽  
Hamid Khavasi ◽  
Fateme Bagherjeri ◽  
Collete Boscovic

AbstractThe reaction of dppm (1,1-bis(diphenylphosphino)methane) with 2-bromo-4-phenylacetophenone and benzyl bromoacetate in chloroform produces new phosphonium salts, [Ph2PCH2PPh2CH2C(O) C6H4Ph]Br (I) and [Ph2PCH2PPh2CH2COOCH2Ph]Br (II). By allowing the phosphonium salts to react with the appropriate base, the bidentate phosphorus ylides, Ph2PCH2PPh2=C(H)C(O)C6H4Ph (III) and Ph2PCH2PPh2=C(H)C(O)OCH2Ph (IV), were obtained. The reaction of these ligands with mercury(II) halides in dry methanol led to the formation of the mononuclear complexes {HgX2[(Ph2PCH2PPh2C(H)C(O)C6H4Ph)]} (X = Cl (V); X = Br (VI); X = I (VII)) and {HgX2[(Ph2PCH2PPh2C(H)COOCH2Ph)]} (X = Cl (VIII); X = Br (IX); X = I (X)). The FTIR and 1H, 31P and 13C NMR spectra were studied. The structure of compound III was unequivocally determined by the single-crystal X-ray diffraction technique. Single-crystal X-ray analysis of the {HgBr2[(Ph2PCH2PPh2C(H)C(O)C6H4Me)]} complex (XI) revealed the presence of a mononuclear complex containing the Hg atom in a distorted tetrahedral environment. In all complexes, the ylides referred to above were coordinated through the ylidic carbon and the phosphine atom.


1984 ◽  
Vol 39 (5) ◽  
pp. 618-622 ◽  
Author(s):  
Graham A. Bowmaker ◽  
Cornelia Dörzbach ◽  
Hubert Schmidbaur

The reaction of CuCl2 with equimolar quantities of an ylide R3P=CH2 (1a-c, R=CH3, C2H5, C6H5) in anhydrous tetrahydrofuran at low temperature leads to oxidative coupling, with ethylidene-1,2-bis-phosphonium salts R3P⊕-CH2-CH2-P⊕R3 2X⊖ (2, 3a-c) as high- yield products. The process is interpreted as a one-electron transfer to give radical cations R3P⊕-ĊH2 (II) which subsequently undergo dimerization. The initial counterions CuCl2⊖ (in 2a-c) can be replaced by PF6⊖ (as in 3a-c). (C2H5)3P=CHCH3 (1d) yields the cation (C2H5)3P⊕-*CH(CH3)-*CH(CH3)P⊕(C2H5)3 with two chiral centers as a mixture of diasteromers RR/SS, RS. The ratio of the components is 2,8:1. as evaluated by NMR spectroscopy.The analogous reaction with (C6H5)3P=CHCH3 and (C6H5)3P=C(CH3)2 (1e, f) takes a very different course. Along with minor quantities of (C6H5)3P⊕CH2CH3/(C6H5)3P⊕CH(CH3)2 species, mainly 1-chloroalkyl-phosphonium cations are formed, which were again isolated as the hexafluorophosphates (4a, 4b: [(C6H5)3P⊕CH(CI)CH3]PF6⊕, [(C6H5)3P⊕C(Cl)(CH3)2]Pf6⊖). H-radical trapping from the medium by II ist proposed for the formation of the former, while a two- electron oxidation followed by addition of Cl⊖ is the most plausible mechanism for the generation of the latter


1977 ◽  
Vol 32 (11) ◽  
pp. 1268-1270 ◽  
Author(s):  
Lothar Knoll

Triphenylmethylene- and triphenylethylidenephosphorane react with h5-cyclopentadienyl-dicarbonylironiodide to yield the yellow stable complexes of the type[h5-C5H5Fe(CO)2-CHRP(C6H5)3]I (R = H (1), CH3 (2)).By reaction of 1 and 2 with AgBF4 the corresponding BF4-salts can be isolated. The new compounds are characterized by their 1H NMR, 31P NMR and IR spectra as well as by elemental analysis.


Polyhedron ◽  
2015 ◽  
Vol 87 ◽  
pp. 349-353 ◽  
Author(s):  
Ali Naghipour ◽  
Khadijeh Badpa ◽  
Behrouz Notash

2019 ◽  
Vol 23 (16) ◽  
pp. 1738-1755
Author(s):  
Humaira Y. Gondal ◽  
Zain M. Cheema ◽  
Abdul R. Raza ◽  
Ahmed Abbaskhan ◽  
M. I. Chaudhary

Following numerous applications of Wittig reaction now functionalized phosphonium salts are gaining attention due to their characteristic properties and diverse reactivity. This review is focused on α-alkoxyalkyl triphenylphosphonium salts: an important class of functionalized phosphonium salts. Alkoxymethyltriphenylphosphonium salts are majorly employed in the carbon homologation of carbonyl compounds and preparation of enol ethers. Their methylene insertion strategy is extensively demonstrated in the total synthesis of a wide range of natural products and other important organic molecules. Similarly enol ethers prepared thereof are important precursors for different organic transformations like Diels-Alder reaction, Claisen rearrangement, Coupling reactions, Olefin metathesis and Nazarov cyclization. Reactivity of these α-alkoxyalkylphosphonium salts have also been studied in the nucleophilic substitution reactions. A distinctive application of this class of phosphonium salts was recently reported in the phenylation of carbonyl compounds under very mild conditions. Synthesis of structurally diverse alkoxymethyltriphenylphosphonium salts with variation in alkoxy groups as well as counter anions are reported in literature. Here we present a detailed account of different synthetic methodologies for the preparation of this unique class of quaternary phosphonium salts and their applications in organic synthesis.


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