22836-30-2Relevant academic research and scientific papers
Photochemical transformation of chlorobenzenes and white phosphorus into arylphosphines and phosphonium salts
Gschwind, Ruth M.,Mende, Michael,Scott, Daniel J.,Streitferdt, Verena,Till, Marion,Wolf, Robert
supporting information, p. 1100 - 1103 (2022/02/03)
Chlorobenzenes are important starting materials for the preparation of commercially valuable triarylphosphines and tetraarylphosphonium salts, but their use for the direct arylation of elemental phosphorus has been elusive. Here we describe a simple photochemical route toward such products. UV-LED irradiation (365 nm) of chlorobenzenes, white phosphorus (P4) and the organic superphotoreductant tetrakis(dimethylamino)ethylene (TDAE) affords the desired arylphosphorus compounds in a single reaction step.
Rh-Catalyzed [2 + 2 + 2] Cycloadditions with Benzoquinones: De Novo Access to Naphthoquinones for Lignan and Type II Polyketide Synthesis
Wood, James M.,Da Silva, Eufranio N.,Bower, John F.
supporting information, p. 265 - 269 (2020/01/02)
The first examples of Rh-catalyzed [2 + 2 + 2] cycloadditions between diynes and benzoquinones are described. The method enables de novo and step-economical access to challenging naphthoquinones that are of relevance to lignan and type II polyketide synthesis. The value of the chemistry is demonstrated by a short total synthesis of justicidone.
Modular Access to Substituted Azocanes via a Rhodium-Catalyzed Cycloaddition-Fragmentation Strategy
Shaw, Megan H.,Croft, Rosemary A.,Whittingham, William G.,Bower, John F.
supporting information, p. 8054 - 8057 (2015/07/15)
A short entry to substituted azocanes by a Rh-catalyzed cycloaddition-fragmentation process is described. Specifically, exposure of diverse N-cyclopropylacrylamides to phosphine-ligated cationic Rh(I) catalyst systems under a CO atmosphere enables the directed generation of rhodacyclopentanone intermediates. Subsequent insertion of the alkene component is followed by fragmentation to give the heterocyclic target. Stereochemical studies show, for the first time, that alkene insertion into rhodacyclopentanones can be reversible.
Synthesis of symmetrical and unsymmetrical functionalized arylphosphines from chlorophosphines and organozinc reagents
Le Gall, Erwan,Ben A?ssi, Karima,Lachaise, Isabelle,Troupel, Michel
, p. 954 - 956 (2007/10/03)
A stepwise procedure allowing the formation of symmetrical arylphosphines is described. It relies on the use of preformed functionalized aromatic organozinc reagents to perform arylations of chlorophosphines. Some preliminary results concerning the synthesis of unsymmetrical diarylphenylphosphines through sequential coupling of organozinc species with dichlorophenylphosphine are also reported. Georg Thieme Verlag Stuttgart.
Synthesis of symmetrical triarylphosphines from aryl fluorides and red phosphorus: Scope and limitations
Schull, Terence L.,Brandow, Susan L.,Dressick, Walter J.
, p. 5373 - 5376 (2007/10/03)
The reaction of aryl fluorides with phosphide anion, generated in situ from the reduction of red phosphorus by lithium metal in liquid ammonia, gave symmetrical triarylphosphines in fair to good yields. Phosphonodiamide, sulfonamide, 2-oxazolyl, and nitrile groups were stable to the reaction conditions, while nitro and bromo substituents were not. para-Substituted aryl fluorides gave higher yields than meta-substituted aryl fluorides, and ortho-substituted aryl fluorides failed to react.
A new efficient preparation of polyfunctional phosphines using zinc organometallics
Langer, Falk,Knochel, Paul
, p. 4591 - 4594 (2007/10/02)
The reaction of diorganozines or organozinc halides with chlorophosphines (Ph(n)PCl(3-n)) produces polyfunctional phosphines in high yields. This method has been used to prepare several chiral phosphines in high enantiomeric purity.
A new synthesis of hydrophilic carboxylated arylphosphines
Ravindar,Hemling,Schumann,Blum
, p. 841 - 851 (2007/10/02)
An efficient synthetic procedure for the preparation of versatile functionally substituted arylphosphines from commercially available starting materials is reported together with alternative routes for (carboxyphenyl)diphenyl phosphines.
N-Phenyl-P,P,P-triarylphospha-λ5-azenes, Triarylphosphines, and Triarylphosphine Oxides. Substituent Effects on 15N, 31P, and 13C NMR Spectra
Chou, Whe-Narn,Pomerantz, Martin
, p. 2762 - 2769 (2007/10/02)
The syntheses and 15N, 31P, and 13C NMR spectra of a series of N-phenyl-P,P,P-triarylphospha-λ5-azenes 4 and the 31P and 13C NMR spectra of the corresponding series of triarylphosphines 5 and triarylphosphine oxides 6 are reported.The substituent effects on the chemical shifts can be best accommodated and rationalized by use of a model for system 4 whereby the dipole of the aryl group and its pendant R group polarizes the rest of the molecule.This includes the P and N atoms and phenyl ring, where an electron-withdrawing R group increases the electron density of the P, N, and ipso C-1 while decreasing the electron density on C-3 and C-4 of the N-phenyl ring (Figure 3).A similar polarization pattern for the phosphine oxide series 6 is suggested.In the phosphine series 5, the chemical shift data is consistent with the lone electron pair on the phosphorus atom delocalizing into the aryl rings.The coupling constant data, in particular 1JPN for series 4 and 1JPC for series 4-6, were examined with use of the Hammett monosubstituent parameter (MSP) and the Taft dual-substituent parameter (DSP) approaches.For systems 4 and 6, without a lone electron pair on the phosphorus atom, a better electron-donating substituent increases the one-bond P-C(Ar) coupling constant.On the contrary, in the phosphine series 5, where there is a lone electron pair on the phosphorus, a better electron-withdrawing substituent increases the one-bond P-C(Ar) coupling constant.DSP treatment of 1JPC, and comparing to the few related systems in the literature,shows three types of systems.One, which includes 4 and 6, has an atom, phosphorus in these cases, that does not have a lone pair of electrons attached to the ring to which is attached an atom with a lone pair of electrons.Here, the resonance effect on 1JPC predominates.A second series, which includes phosphines 5, has a lone pair on the atom attached to the aryl ring.In these cases, the resonance effect is ca. 50percent greater than the inductive effect.Finally, the third series, exemplified by two examples from the literature, has a tetrahedral atom (without a lone pair) attached to the aryl ring and this in turn is attached to tetrahedral atoms without lone electron pairs.In these case, the resonance and inductive effects are fairly comparable.
