3-(1-Hydroxycyclohexyl)-2-propynenitrile reacts with tris[2-(4-pyridyl)ethyl]phosphine oxide to form mono-, bis-and tris{5-spirocyclohexyl-4-cyanomethylene-1,3-oxazolidine[3,2-a]-2-[4-(1,2-dihydropyridyl)]ethyl}phosphine oxides.Activated acetylenic compounds, in particular the methyl ether of acetylenecarboxylic acid and the dimethyl ether of acetylenedicarboxylic acid, form (normally, in low yields) heterocyclic compounds such as quinolizines, indolizines, cyclazines, by reaction with pyridine and pyridine derivatives. 1,2 Recently, 3 we have found that the reaction of pyridine and its derivatives with nitriles of a,bacetylenic g-hydroxy acids (the reactivity of which has been discussed in reviews 4,5 ) proceeds in high yields under mild conditions (r.t., without solvents and catalysts) involving the hydroxy group to give a new heterocyclic system, oxazolidinedihydropyridines. In the present work we have used the reaction for the synthesis of polyfunctional phosphine oxides from nitriles of a,b-acetylenic ghydroxy acids and recently available tris[2-(4-pyridyl)ethyl]phosphine oxide. 6,7 The present work reports some results of the research into the reaction of tris[2-(4-pyridyl)ethyl]phosphine oxide (1) with 3-(1-hydroxycyclohexyl)-2-propynenitrile (2) performed in order to obtain new organophosphorus compounds containing pyridine and oxazolidine rings, which are regarded as rather promising intermediates for organic synthesis and biologically active compounds. The reaction of hydroxycyclohexylpropynenitrile 2 with phosphine oxide 1 occurs at 20-25 °C in acetonitrile and a molar ratio of 1:10 (1:2) for 10 hours to form selectively tris{5-spirocyclohexyl-4-cyanomethylene-1,3-oxazolidine[3,2-a]-2-[4-(1,2-dihydropyridyl)]ethyl}phosphine oxide (3) in 90% yield (Scheme).The initial stages are characterized by the formation of zwitterionic intermediates A, B 3 further stabilized by closure to a 1,3-oxazolidine ring.Under comparable conditions (MeCN, 20-25 °C, 10 h) at a three-fold molar excess of the nitrile 2 the formation of mono{5-spirocyclohexyl-4-cyanomethylene-1,3-oxazolidine[3,2-a]-2-[4-(1,2-dihydropyridyl)]ethyl}phosphine oxide (4), bis{5-spirocyclohexyl-4-cyanomethylene-1,3-oxazolidine[3,2-a]-2-[4-(1,2-dihydropyridyl)]ethyl}-phosphine oxide (5) and tris{5-spirocyclohexyl-4-cyanomethylene-1,3-oxazolidine[3,2-a]-2-[4-(1,2-dihydropyridyl)]ethyl}phosphine oxide (3) occurs (total yield 55%, 3:4:5 ratio = 2:3:4) (Figure 1).An increase in the reaction time of up to 36-40 hours does not affect the ratio of isomers. It was not possible to separate the adducts (column chromatography, fractional crystallization). The reaction of phosphine oxide 1 with acetylene 2 in octane (1:2 molar ratio = 1:3, 20-25 °C) needs more time (up to 60 h) to be completed. In this case the ratio of adducts 3-5 does not change, the total yield being 40%. SchemeDownloaded by: University of Pittsburgh. Copyrighted material.

New catalytic systems CsFMOH (M = Li, Na) were developed for the synthesis of alkyl vinyl ethers comparable in efficiency to cesium alcoholates. The addition of primary and secondary alcohols to acetylene occurs in the presence of these systems at the atmospheric (DMSO, 100°C) or at enhanced (without solvent, 135 140°C) acetylene pressure and affords alkyl vinyl ethers in up to 93% yield. * For communication XII see [1]. The systematic investigation of alcohols vinylation with acetylenes discovered by A.E. Faworsky [2] and further developed by W. Reppe [3] and M.F.Shostakovskii [4] provide deeper theoretical insight into the nucleophilic additions to the triple bond [5] and constant refining of the synthesis of vinyl ethers of versatile structures [3 12].Here the main trend in stimulating vinilation reaction is the application of superbasic systems, like alkali metal hydroxidepolar solvent lacking hydroxy groups (DMSO, N-methylpyrrolidone, HMPA) [5, 712], or alkali metal alcoholateLewis base (Crown ether)solvent lacking hydroxy groups (hydrocarbon) [13,14].We report here on the application of highly basic systems CsFMOH and CsFMOHDMS (M = Li, Na) as efficient catalysts to alcohols vinylation.In [15,16] it was shown by an example of 1-heptanol vinylation under enhanced and atmospheric acetylene pressure in the presence of alkali metal hydroxides that the catalysts under investigation fit to the following series according to the decreasing efficiency:The comparison of the catalytic activity of KOH hydrates (2KOH·H 2 O and KOH·H 2 O) confirmed the known [4,7] negative effect of water on the vinylation process. Consequently, the use of anhydrous alkali metal hydroxides, first of all of CsOH would considerably accelerate the vinylation of the hydroxy compounds. However the preparation of anhydrous cesium and rubidium is a laborious process. Usually azeotropic removal of water is used with an appropriate high-boiling solvent (octane, toluene). The present article contains findings evidencing the possibility of a successful application to the vinyl ethers synthesis of a catalytic system CsFMOH (M = Li, Na) where the anhydrous CsOH is formed directly in the course of vinylation. This system possesses significant advantages compared to traditional vinylation catalysts like sodium and potassium hydroxides.The high catalytic efficiency of the system developed is apparently due predominantly to the exchange between the lithium or sodium hydroxides and cesium fluoride resulting in cesium hydroxide and sparingly soluble lithium or sodium fluorides.The nature of the alkali metal cation in the MOH (where M = Li, Na) used in the catalytic couple CsF MOH did not virtually affect the rate of vinylation in keeping with the preliminary occurrence of the exchange reaction and with the actual catalysis of alcohol vinylation by the arising cesium hydroxide. The formation of sparingly soluble lithium and sodium fluorides shifts the exchange equilibrium to the right. Therewith the better solubility in alcohols of NaOH compared to...

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The major product of the reaction of benzyl chloride with red phosphorus in the system concentrated aqueous KOH3dioxane3phase-transfer catalyst (43395oC, Ar) is tribenzylphosphine oxide (yield up to 61%). Under similar conditions, phosphorylation of benzyl chloride with white phosphorus occurs differently, yielding dibenzylphosphine oxide as major product. Conditions are found for preparative synthesis of dibenzylphosphine from phosphine and benzyl chloride in the system KOH3DMSO.