Phosphonic acid nitriles

Addition of the alcohol 42 to a solution of BF3 Et20/TMSCN in DCM provided the nitrile 43 in 83% yield. Hydrolysis of nitrile 43 then furnished amide 44 in 85% yield. Demethylation of the methoxyindole 44 with BBra in DCM provided the hydroxyindole 45 in 80% yield. This was followed by alkylation of 45 with the bromide 46 under phase transfer conditions to provide the phosphonate ester 47 and subsequent cleavage of the methyl ester by TMS-I furnished trimethylsilyl phosphonic acid 48, which upon alcoholic workup afforded LY311727. 

Diaikanol aminoalkyl phenols as admixtures enhance the strength [675]. The additives are useful in very small amounts and do not affect the initial properties of the fluid. The strength additive does not cause set acceleration or early set strength enhancement but provides enhanced compressive strength of the cement in later stages. Addition of small amounts of potassium ferricyanide and nitrile-trimethyl phosphonic acid promotes the formation of complex compounds and thus increases the strength of cement rock [1771]. 

N. A. Okishev, A. G. Ivanov, and I. V. Karpenko. Plugging solution for oil and gas wells with increased sedimentation stability—containing Portland cement, nitrile trimethyl phosphonic acid, polyoxyethylene, water-soluble cationic polyelectrolyte and water. Patent RU 2039207-C,1995. 

Plugging solution contains Portland cement, sodium sulphate, potassium ferricyanide and nitrile-tri-methyl-phosphonic acid. Patent SU 1700204-A, 1991. 

P. F. Tsytsymushkin, S. R. Khajmllin, A. P. Tamavskij, Z. N. Kudryashova, and B. V. Mikhajlov. Plugging solution contains Portland cement, sodium sulphate, potassium ferricyanide and nitrile-tri-methyl-phosphonic acid. Patent SU 1700204-A, 1991. 

Several communications, summarized in Scheme 14, have described the synthesis of many amino-substituted dialkylphosphinic acids and phosphonic acids, and also many similarly substituted hydrogenphosphinic acids. Alkylation of the phosphinates (272) (R = H or Me, = Et, R = H) yields the corresponding (273) which, in a single step, are convertible into the useful intermediates (274). With 1,2-unsaturated nitriles, for example, the (3-aminopropyl)phosphinic acids... 

Organic phosphorus-containing compounds (mono and dialkyl esters(C2 — Cio) of phosphoric acid, hydroxyethylidene-diphosphonic acid, nitrile-tris (methylene phosphonic acid) are mainly used as ingredients of polymer coatings. They are related to Cl of the anodic-passivating type [63]. 

Acceptors, a, P-Unsaturated ketones Esters Aldehydes, Amides Carboxylic acids Nitriles Sulphoxides Phosphonates and Phosphoranes. 

Nitrile oxides 95Dahl Phosphonic acids 92Dahl... 

Figure 9-12. Nyquist plots of mild steel in a model solution with different inhibitors after 30 min nitrile (triacetic acid) (NTA) phospho-nomethyl-iminodi (acetic acid) (MPIDA), di(phosphonomethyl)-glycine (DMPG), nitrilotri(methyl-phosphonic acid) (ATMP).

In the review period, most syntheses of phosphonic acids and their derivatives involved simple organophosphorus reagents, like diallq l and trialkyl phosphites that were widely used in reactions with aHqmes and alkenes including bromoalkenes to obtain alkenyl and allqmylphospo-nates as well as with imines, ketimines, ketones, aldehydes and nitriles to afford imino- and aminophosphonates, and hydroxyphosphonates. Two or more component reactions were also utilised in these syntheses. 

Amines. Reaction of PCI3 with quaternary ammonium salts yields phosphaindolizines and thiazolodiazaphospholes. Imines produce phosphonates whereas hydrazones are converted to pyrazoles, indoles, and nitriles. Nitrones undergo rearrangement to secondary or tertiary amides and primary alkylnitro compounds are reduced to nitriles (eq 3). Diazonium salts are transformed to phosphonic acids. ... 

A multitude of 1,4-dicarbonyls (1) undergo the Paal-Knorr reaction with and ranging from H to alkyl, aryl, carbonyl, nitrile, and phosphonate, while R and R vary between H, alkyl, aryl, trialkylsilyl, and O-alkyl. Protic acid catalysts are typically used with sulfuric, hydrochloric, and p-toluenesulfonic acids the most popular. Conversion to the furan takes place either at room temperature or upon heating with reaction times varying from five minutes to 24 hours and yields ranging from 17-100%. 

In 2006, our research group reported a novel MCR based on the reactivity of a-acidic isocyano esters (1) toward 1-azadienes (84) generated by the 3CR between phosphonates, nitriles, and aldehydes [169]. Remarkably, the dihydropyridone products (85) for this 4CR contained the intact isonitrile function at C3. The exceptional formation of the 3-isocyano dihydropyridone scaffold can be explained by the Michael-attack of the a-deprotonated isonitrile (1) to the (protonated) 1-azadiene (84), followed by lactamization via attack of the ester function by the intermediate enamine. Although in principle the isocyano functionality is not required for the formation of the dihydropyridone (85) scaffold, all attempts using differently functionalized esters (e.g., malonates, ot-nitro, and a-cyano esters) gave lower yields of the dihydropyridone analogs [170] (Fig. 26). 

C-Acylations of C,H-acidic compounds have also been realized on insoluble supports. The few examples that have been reported include the C-acylation of support-bound ester enolates with acyl halides [9], Claisen condensations of polystyrene-bound ketones with benzoic acid esters, the C-acylation of nitriles with acyl nitriles or anhydrides, and the C-acylation of phosphonates with acyl halides (Entries 5-9, Table... 

A large part of the usefulness of the Michael reaction in organic synthesis derives from the fact that almost any activated alkene can serve as an acceptor7—a, 3-unsaturated ketones, esters, aldehydes, amides, acids, lactones, nitriles, sulfoxides, sulfones, nitro compounds, phosphonates, phosphoranes, quinones,... 

Several new routes involve formation of one carbon-carbon bond in pre-formed substrates. Palladium-catalyzed cyclization of /3-hydroxyenamine derivatives has been employed in a route to substituted pyrroles and 4,5,6,7-tetrahy-droindoles with multiple substituents by formation of the C-3-C-4 bond as the key feature, as illustrated by construction of the molecule 534 (Equation 146) <2006T8533>. Zinc perchlorate-catalyzed addition of alcohols to the nitrile functionality of a-cyanomethyl-/3-ketoesters, followed by annulation gave access to a series of substituted ethyl 5-alkoxypyrrole-3-carboxylates <2007T461>. Similar chemistry has also been used for synthesis of a related set of pyrrole-3-phosphonates <2007T4156>. A study on preparation of 3,5,7-functionalized indoles by Heck cyclization of suitable A-allyl substituted 2-haloanilines has also appeared <2006S3467>. In addition, indole-3-acetic acid derivatives have been prepared by base induced annulation of 2-aminocinnamic acid esters (available for instance from 2-iodoani-lines) <2006OL4473>. 

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