Phosphonic syntheses with

ARBUZOV MICHAELIS Phosphonale Synihesis Ni catalyzed phosphonate synthesis from phosphites and aryl halides Reaction of alkyl halides with phosphites proceeds without nickel salts... 

The synthesis and surface-active properties of higher hydroxyalkanediphos-phonates are discussed in Ref. 67. Phosphorus-containing betaines as hydrolytically stable surfactants, free from alkali salt impurities, were prepared by a reaction of amidoamines and equimolar amounts of phosphonate esters with 1.5-2 eq of formaldehyde at 60-140°C in a polar solvent [72]. 

Hoveyda and coworkers [142] developed the Cu-catalyzed allylic substitutions of phosphonate derivatives with pyridinyl peptide structures as efficient ligands. The structure of the ligands was chosen through synthesis, and analysis of libraries. Optimized compounds were used as ligands for the... 

Intramolecular condensation of phosphonate carbanions with carbonyl groups carried out under conditions of high dilution have been utilized in macrocycle syntheses. Entries 7 and 8 show macrocyclizations involving the Wadsworth-Emmons reaction. Entries 9 to 11 illustrate the construction of new double bonds in the course of a multistage synthesis. The LiCl/amine conditions are used in Entries 9 and 10. 

A convenient synthesis of half-derivatives of thiophosphonic acids starts from the corresponding phosphonic dichloride, with isolation of the trimeric thiophosphonic anhydride (53)44a and subsequent reaction of this with amines and alcohols.446... 

Among those phosphonates used successfully in alkene synthesis with aromatic aldehydes were (114),106 (115),107 (116),108(117),109 and(118).110 The stereochemical... 

Phosphonate synthesis from the reaction of aikyi haiides with phosphites. 

Intramolecular condensation of phosphonate carbanions with carbonyl groups carried out under conditions of high dilution has been utilized in macrocycle synthesis (entries 8 and 9 in Scheme 2.17)... 

Scheme 2.2.5.6 Comparison of GPO-catalyzed enzymatic synthesis with a new chemical synthesis of phosphonate analogue 14, which is bio-isosteric with 1.

The methodology of the catalytic asymmetric aldol reaction has been further extended to the aldol-type condensation of (isocyanomethyl)phosphonates (12) with aldehydes, providing a useful method for the synthesis of optically active (l-aminoalkyl)phosphonic acids, which are a class of biologically interesting phosphorous analogs of a-amino acids (Scheme 8B1.6) [21,22], Higher enantioselectivity and reactivity are obtained with diphenyl ester 12b than with diethyl ester 12a (Table 8B1.6). 

Wittig-Homer reactions.3 The reaction of the phosphonate 2 with the aldehyde 1 under literature conditions gives the fraras-stilbene 3 in only about 10% yield. Addition of 15-crown-5 raises the yield to 45%. This step was used in a synthesis of pallescensin E (4), a furanosesquiterpene in a marine sponge. 

The gold-catalyzed aldol reaction has been successfully applied to the asymmetric synthesis of (l-aminoalkyl)phosphonic acids, phosphonic analogs of a-amino acids (Scheme 2-57) [80, 81]. The reaction of (isocyanomethyl)phosphonates 65 with... 

The use of anions derived from a phosphine oxide (132) or a diethyl phosphonate (133) to form al-kenes was originally described by Homer.Although these papers laid the foundations for the use of phosphoryl-stabiliz carbanions for alkene synthesis, it was not until Wadsworth and Emmons published a more detailed account of the general applicability of the reaction that phosphonates bet e widely used. Since the work of Wadsworth and Emmons was significant and crucial to the acceptance of this methodology, the reaction of a phosphonate caibanion with a carbonyl derivative to form an alkene is referred to as a Homer-Wadsworth-Emmons reaction (abbreviated HWE). The phosphine oxide variation of the Wittig alkenation is called the Homer reaction. 

Boutagy, J., Thomas, R. Olefin synthesis with organic phosphonate carbanions. Chemical Reviews (Washington, DC, United States) 1974, 74, 87-99. 

An analogous approach was used in a stereoselective synthesis of /Tamino-a-hydroxy phosphonates [33]. Reduction of corresponding a-keto phosphonate substrates with borane-dimethylsulfide complex aided by oxazaborolidine catalysis afforded a mixture of diastereomers, but significant diastereoselectiv-ity was achieved using catecholborane as the reductant in toluene at -60 °C. 

Balczewski, P, and Mikolajczyk, M., Free radical reaction of a-haloalkylphosphonates with alkenes and alkynes. A new approach to modified phosphonates. Synthesis, 392, 1995. 

Burgos-Lepley, C.E., Mizsak. S.A., Nugent, R.A., and Johnson, R.A., Tetraalkyl oxira-nylidenebis(phosphonates). Synthesis and reactions with nucleophiles, J. Org. Chem., 58,4159, 1993. 

Arbuzov, B.A., and Lugovkin, B.P., Synthesis of esters of phosphonic acids containing heterocyclic radicals. Part 2. Ethyl esters of phosphonic acids with oxygen-bearing heterocyclic radicals, Zh. Obshch. Khim., 22, 1193, 1952 Chem. Abstr., 47, 4871c, 1953. 

Schaumann. E.. and Grabley, EE, Thioketene synthesis. Part 3. Reactions of phosphonate carbanions with carbon disulfide, Liebigs Ann. Chem., 1715, 1979. 

Sawamnra, M., Hamashima, H., and Ito, Y., Rhodium-catalyzed enantioselective Michael addition of (l-cyanoethyl)phosphonate. Synthesis of optically active phosphonic acid derivatives with phosphorussubstituted quaternary asymmetric carbon center, Bull. Chem. Soc. Jpn., 73, 2559, 2000. 

Pudovik, A.N., and Krupnov, G.P., New method of synthesis of esters of phosphonic and thiophosphonic acids. Part 36. Synthesis of derivatives of phosphonic acids with cyclic radicals in the ester groups, Zh. Obshch. Khim., 31, 4053, 1961 J. Gen. Chem. USSR (Engl. Transl), 31. 3782, 1961. 

Rosini, G., Baccolini, G., and Cacchi, S., Reactions of 1-oxoalkanephosphonate tosylhydrazones with sodium borohydride. New synthesis of dimethyl alkanephosphonates and dimethyl 1-diazoalkane-phosphonates. Synthesis, 44, 1975. 

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