Phosphorus, alkylation cyclic acids

The complex of tartaric acid and antimony (emetic) was described three centuries ago. Nevertheless, the structure of this compound has been elucidated these last fifteen years by X-ray diffraction ( 1 ). In fact, emetic presents a binuclear cyclic structure. Many authors mentioned similar complex with transition metals (vanadium (2), chromium (3)) or metalloids (arsenic (4), bismuth (5)). Emetic with phosphorus was not mentioned. Nevertheless, tartaric acid or alkyl tartrates has been utilized in phosphorus chemistry tartaric acid reacts with trialkyl phosphites giving heterocyclic phosphites (6). Starting from alkyl tartrates, we prepared spirophosphoranes with a P-H bond and sixco-ordinated compounds (7). With unprotected tartaric acid, many possibilities appear condensation as a diol, as a di(oc-hydro-xyacid), or even as a 8-hydroxyacid. 

The reagent does not replace nitrogen atoms, and N-alkyl or N-aryl anthranilic acids yield 2,l-benzisothiazoline-3-thiones (94) on heating with phosphorus pentasulfide in xylene. Curiously, when alkyl iV-arylanthranilates are treated in the same way, only a very small proportion—less than 10%— of 94 is obtained. The major product (80%) is the cyclic phosphorus-containing compound (95), the identification of which gives some clue about the structures of possible intermediates.122... 

Rather high (80-90%) yields of dihydrodiazepines are observed when the reaction is carried out on a MgO surface in the presence of phosphorus chlor-oxide [17]. In this manner some dihydrobezodiazepine derivatives 78 and 80 with alkyl substituents are obtained (Scheme 4.25). It should be noted that high product yields are also observed in the reactions of o-PDA with cyclic ketones (e.g., cyclopentanone, cyclohexanone and cycloheptanone), which is not typical of routine acid catalysis [14, 99]. 

Carboalkoxy acyl halides are made from mono esters of dibasic acids and thionyl chloride or phosphorus pentachloride. Examples are numerous. Halides with the ester group in the beta position are unstable to prolonged heating. Alkyl halide is eliminated with the formation of an anhydride. Under certain conditions a rearrangement occurs in the preparation of ester acid chlorides. The product obtained is a mixture of the expected compound and its isomer in which the ester and acid chloride groups are interchanged, viz., ROjCCHR (CI ) CO,H — RO,C(CH,) CHR COQ. The cyclic anhydride is a likely intermediate. ... 

The five membered cydic 1,3-dioxolane (CHjOCHjCHjO) can be polymerised by a variety of catalysts including sulphuric acid (P7), perchloric acid (98), phosphorus pentachloride (PP) and alkyl aluminium compounds with water as a co-catalyst (100). The effect of the catalyst boron trifluoride diethyl etherate on the polymerisation of 1,3-dioxolane has also been studied and it has been found that equilibrium between monomeric 1,3-dioxolane and poly(l, 3-dioxolane) is set up in both the undiluted polymer and in solution (101-104). Controverf has arisen as to whether the equilibrium is between cyclic monomer and cyclic polymer (98) or between cyclic monomer and chain polymer (104). 

It is evident that the interaction of a phosphorus(III) triester and the alkylating species RX can be pictured as an S 2 process (reaction 2) or, for those alkylating reagents capable of forming a carbocation, as an S l process (reaction 3). Several reactions testify to the importance of carbocationic carbon for the Michaelis-Arbuzov reaction in pursuance of its normal course they include the ease of reaction of cyclopropene dihalides, already encountered, and the ready formation of complexes with species having particularly weakly nucleophilic counter ions. Phosphonic acid formation also takes place with cyclic azonium salts and related ions. 9-Chloroacridine reacts with triethyl phosphite to afford a product thought to be the bisphosphonic acid ester 49 The related phosphonic esters 51 are obtainable when the onium salts 50 (X = NH, NR, O or S) are treated with trimethyl... 

In principle, the reaction between a dihaloalkane (9) and a phosphorus(III) ester (10 (R = alkyl, aryl or alkoxy) initially affords the haloalkyl compound 11 the use of a trialkyl phosphite would thus lead to an (co-haloalkyl)phosphonic diester 11 (R = alkoxy, R = alkyl), whilst that of a phosphonite diester (10 R = alkyl, aryl) would afford an (co-haloalkyl)alkyl(or aryl)phosphinic ester. Depending on the ratio of reactants, further reaction might then take place (pathway A), resulting in the formation of the compounds 12. Depending also on n, and on the reaction temperature, the alternative pathway B may be followed the products are then cyclic phosphonic or phosphinic acid derivatives 13, and examples following both reaction pathways have been discussed (chapter 2, Section A). 

Cationic polymerization of cyclic trivalent phosphorus compounds, initiated by alkyl halides, Lewis acids, Friedel-Crafts catalysts, and/or esters, was reported for various cyclic phosphites (34), " " phosphonites (35), " phosphoramidites (36), cyclic phos-phanols (37), " and cyclic phosphanethiols (38). °° Mel, PhCH2Br, and CF3S03Me were mainly used as initiators. The resulting polymers had molar mass not... 

Reaction with Thiocarboxylic Acids, Phosphoric Acids, Sulfonic Acids, and their Derivatives. Thiocarboxylic acids, - dithiocarboxylic acids, and dimethyldithiocarbamic acid zinc salt, as well as various phosphorus oxyacids and phosphorus thioacids, can also be utilized. a,o)-Mercapto alcohols form cyclic thioethers whereas thiols react with both DEAD and TPP-DEAD to form disulfides. 2-Mercaptoazoles also react with alcohols in the presence of DEAD and TPP. Although arenesulfonic acids do not enter into the reaction, a combination of DEAD-TPP with methyl p-toluenesulfonate as a nucleophile carrier gives the corresponding alkyl sulfonates (eq 14). Altema-... 

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