33838-34-5

Upstream product

• 39837-64-4 menthyl methylphenylphosphinate 
• 100-44-7 benzyl chloride 
• 91606-80-3 ethyl hyponitrite 
• 34868-25-2 R(+)-Benzyl-methyl-phenyl-phosphin 
• 917-64-6 methyl magnesium iodide 
• 118643-74-6 (1S,7S)-9,9-dimethyl-4-phenyl-3,5,8,10,4-tetraoxaphosphabicyclo<5.3.0>decane 
• 620-05-3 iodomethylbenzene 
• 118643-73-5 (5S,6S)-dimethoxy-2-phenyl-1,3,2-dioxaphosphacycloheptane 
• 6389-79-3 methyl methylphenylphosphinate 
• 6921-34-2 benzylmagnesium chloride 
• 23275-37-8 Benzyl-methyl-phenyl-phosphin 
• 1344732-73-5 benzylphenyl(2-pyridylmethyl)phosphine oxide 
• 20335-99-3 benzyl (phenyl)phosphine oxide 
• 74-88-4 methyl iodide 

Downstream Products

• 23275-37-8 Benzyl-methyl-phenyl-phosphin 

Relevant academic research and scientific papers

Ni-Catalyzed Enantioselective Benzylation of Secondary Phosphine Oxide

A nickel-catalyzed benzylic substitution of secondary phosphine oxide was described, affording the dialkylated P-stereogenic tertiary phosphine oxides with high to excellent enantioselectivities. The reaction was performed under mild conditions with commercially available benzyl chlorides and bench stable secondary phosphine oxides, exhibiting broad functional group tolerance. It represented a practical example for the preparation of P-stereogenic phosphine compounds.

Sodium in liquid ammonia - A versatile tool in modifications of arylphosphine oxides

A simple and practical method for modifications of tertiary arylphosphine oxides based on their reaction with sodium in liquid ammonia is presented. Depending on the structure of the starting compounds, either dearomatisation of the phenyl substituent or cleavage of a P-aryl bond from phosphorus atom can be selectively performed and the corresponding (1,4-cyclohexadien-3-yl)phosphine oxides or secondary phosphine oxides were obtained in good to excellent yields.

Asymmetric Synthesis of Phosphine Oxides with the Arbuzov Reaction

The Arbuzov reaction of (5S,6S)-dimethoxy-2-phenyl-1,3,2-dioxaphosphacycloheptane with various alkyl halides produced acyclic phosphinates in a moderate to high diastereomer excess.The same reaction of (1S,7S)-9,9-dimethyl-4-phenyl-3,5,8,10,4-tetraoxaphosphabicyclodecane with the alkyl halides needed the more vigorous reaction conditions and gave phosphinates in a low diastereomer excess.These phosphinates were converted into optically active phosphine oxides.

Chromatographic Resolution of Racemic Compounds Containing Phosphorus or Sulfur Atom as Chiral Center

Racemic compounds containing a phosphorus or a sulfur atom as a chiral center were resolved by high-performance liquid chromatography on optically active (+)-poly(triphenylmethyl methacrylate).The resolved compounds include insecticides such as O-ethyl O-(4-nitrophenyl)phenylphosphonothionate (EPN), O-(4-cyanophenyl)-O-ethyl phenylphosphonothionate (cyanofenfos), and 2-methoxy-4H-1,3,2-benzodioxaphosphorin 2-sulfide (salithion).

SYNTHESE DIRECTE DE PHOSPHINES TERTIARIES RACEMIQUES ET DE CHLOROPHOSPHINES DISSYMETRIQUES

Racemic tertiary phosphines are obtained from dichlorophenylphosphine by a "one pot" synthesis in two steps: (1) condensation of one equivalent of an organocadmium, and (2) substitution of the second chlorine by another organometallic compound.The phosphines liberated from the resulting complexes can be stabilised by direct complexation with cuprous salts.The monochlorophosphines can be isolated in the first stage when their cadmium complexes are submitted to ligand exchange with pyridine.

PHOSPHORORGANISCHE VERBINDUNGEN 103. Die ozonolytische Desulfurierung von Thiophosphorylverbindungen: P=S -> P=O

The sulfur atom in thiophosphorylgroups P=S is exchanged by oxygen with retention of configuration according to (1) and (2) as a result of an interaction of the P=S groups with ozone (Table 1 and 2).In dithiophosphinicacidesters only the thionosulfur is easily replaced by oxygen using ozone.The absolute configuration of the enantiomeric methyl-phenyl-phosphinicacid-p-nitrophenylesters 7 an 8 is controlled on the basis of the reaction circle (4).Serine enzymes are blocked by the phosphinicacidesters 7 and 8 by a rate factor of about 60 faster than by the corresponding thionophosphinicacidesters 5 and 6.The phosphinicacidesters 7 (and 8) have a high O-selectivity in competing reactions (7:n-BuOH:n-BuNH2 = 1:1:1) in contrast to the thionophosphinicacidesters 5 (and 6) with no selectivity (ester:amide = 4:6).

REACTIONS OF ETHOXY RADICALS WITH OPTICALLY ACTIVE TERTIARY PHOSPHINES. STEREOCHEMISTRY OF THE SUBSTITUTION PROCESS AND THE QUESTION OF PERMUTATION MODES FOR THE POSSIBLE PHOSPHORANYL RADICAL INTERMEDIATES.

The reactions were shown to yield substitution products MePhPOEt and n-PrMePOEt, respectively. Both reactions occur with net inversion of configuration at phosphorus. Optical yields are very sensitive to reaction times and conversions, because the product phosphonites are readily racemized by EtOH formed during reaction. If indeed these substitutions take place via phosphoranyl radicals, then the stereochemistry for reaction of (-)(S)-2 is consistent with the pi * electronic configuration and presumed tetrahedral geometry normally assigned to phenyl-substituted phosphoranyl radicals. Potential trigonal-bipyramidal intermediates are considered with the assumption that the EtO multiplied by (times) in initial adducts is apical and that the PhCH//2 departs exclusively from the apical position.

Optically Active Phosphines. Facile Preparation of the Optically Active n-Propylmethylbenzyl- and Methylphenylbenzylphosphine Oxides as Precursors to the Corresponding Tertiary Phosphines

The optically active phosphine oxides MePhP(O)CH2Ph (6) and n-PrMeP(O)CH2Ph (9) are readily prepared by a new route from the easily available, essentially optically pure, O-isopropyl S-alkyl methylphosphonothioates 4 and 7.Two successive Grignard reactions give 6 in 52-55percent and 9 in 18-24percent overall chemical yields.Reductions of 6 and 9 with PhSiH3 afford the corresponding optically active phosphines MePhCH2Ph (1) and n-PrMePCH2Ph (2) of optical purities (45-70percent and 53-57percent, respectively) which are quite suitable for studies of the stereochemistries of reactions occurring at phosphorus.The relative ease of the procedure and the fact that both enantiomers are equally readily available especially recommend this route for the preperation of 1.Moreover, no other experimentally detailed, published method for the preparation of an optically active trialkylphosphine such as 2 in reasonably high optical purity is available.The route to phosphine 1 depends on the use of potentially tridentate ligand (SCH2CH2OCH2CH2OCH2CH3) on phosphorus which activates 4 toward reaction with PhMgBr and also allows CH3CH2OCH2CH2OCH2CH2 to be selectively displaced.Quite surprisingly, this displacement occurs with inversion of configuration at phosphorus by contrast to the retentive stereochemistry normally observed on reaction of O-alkyl S-alkyl methylphosphonothioates with Grignards.Evidence is also presented for the potential generality of this method for the preparation of optically active dialkylphenyl- and trialkylphosphines.