Phosphorohalidates

Trimethylsilyl phosphorohalidates (6) and (7) have been synthesized from phosphoryl dihalogenofluoride (8) and hexamethyldisiloxane (9). An alternative approach to (7) using bis(trimethylsilyl) phosphorofluoridate (10) has been also elaborated (Scheme 1). Compounds (6) and (10) are involved in a new synthesis of bis(trimethylsilyl) diphosphorodifluoridate (11). ... 

Gajda, T., Zwierzak, A. Phase-transfer-catalysed halogenation of di-t-butyl phosphite, preparation of di-f-butyl phosphorohalidates. Synthesis 1976, 243-244. 

R = O-alkyl, n= 1) in the same way, diethyl phenylphosphonite affords 11 (R = Ph, R = Et, = 1, X = I). Bromoform and iodoform, although reactive to trialkyl phosphites, tend to yield alkyl halide, dialkyl hydrogenphosphonate and dialkyl phosphorohalidate, but (halomethyl)phosphonate esters are not obtained. With tetrahalomethanes, particularly those based on two or more different halogens, a more interesting picture is presented. Triethyl phosphite and tetrabromomethane are reported to yield EtBr quantitatively but... 

Htdogemtiou. Di-/-butyl phosphorohalidates (X = Q, Br) can be prepared in ca. 90% yield by phase-transfer catalyzed halogenation of di-r-butyl phosphite with ecu or CBri (equation I). This reaction failed wi th other dialkyl phosphites. ... 

All tetrahedral halophosphates (phosphorohalidates) can in principle be prepared by reacting a phosphorus oxyhalide with the appropriate amount of alcohol or phenol (5.331, 5.332). With phos-phoryl chloride, the reaction proceeds smoothly at room temperature when R is a primary aliphatic alcohol, provided the hydrogen chloride can be removed. Usually these reactions are carried out in an inert solvent at or below room temperature with a suitable base added to remove the HCl. 

Sodium hydroxidelbenzyltriethylammonium chloride Phosphorohalidates from dialkyl phosphites and carbon tetrahalides... 

The thienamycin precursor is then prepared by phosphonylation with phosphorohalidates in a substantially inert solvent containing a suitable tertiary amine. The function of the base is to keep the reaction medium... 

Halogenophosphoric acid esters s. Fluorophosphoric acid monoesters, Phosphorohalidates Halogenophosphorus compounds... 

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