There have been two effects of the external electric field influence on the diffraction efficiency of reconstructed holograms observed in the films of copolymers 4-[(2-nitrophenyl)diazenyl]phenyl methacrylate with octylmethacrylate, when holographic recording of the plane wave front for parallel and orthogonal orientation of polarization vectors of light beams was performed at room temperature. After recording at exposure with small energies, diffraction efficiency in the electric field formed by corona discharge decreases, while with large exposure energies, it increases. Diffraction efficiency and recording velocity are higher in copolymer with lower softening temperature. The first effect is caused by reorientation of the dipole moments of azobenzene isomer fragments in the electric field, while the growth of diffraction efficiency is explained by the increase in the amplitude of regular geometric relief of the film surface, which appears during formation of the polarization hologram.

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The reactions of esters 1 and dialkylamides 8 of 3-phosphorylpropionic acids with Grignard reagents 6 in the presence of titanium tetraisopropoxide 5 or methyltitanium triisopropoxide 11 give 1-substituted and 1,2-disubstituted phosphorylated cyclopropanols 7 and cyclopropylamines 12 in moderate to very good yields (37-71 and 39-86%, respectively). These useful transformations convincingly demonstrate the wide functional group compatibility and versatility of this new carbonyl group cyclopropanation.A wide variety of cyclopropane derivatives with hydroxy, amino and carboxyl functionalities show interesting and important biological effects. 1 The role of the phosphorus atom in providing vital functions in both animals and plants is also well known. 2-4 Although a variety of phosphoryl-substituted cyclopropane derivatives have been prepared, mostly by addition of carbenes to phosphorylsubstituted alkenes, 5 no convenient synthesis of any oligofunctional cyclopropyl compounds containing both the pharmacophoric phosphoryl and hydroxy or amino moieties has been reported.The reactions of alkanecarboxylates and N,Ndialkylalkanecarboxamides with Grignard reagents mediated by titanium tetraisopropoxide or methyltitanium triisopropoxide are simple and versatile ways to prepare 1-substituted and 1,2-disubstituted cyclopropanols 6 and cyclopropylamines. 7 Although it has long been known that phosphorus acid esters do react with Grignard reagents to yield tertiary phosphine oxides, 8,9 these reactions proceed much more slowly than those of a carbonyl or alkoxycarbonyl group. 10 It appeared, therefore, reasonable to expect that the carbonyl groups in the easily accessible methyl phosphorylalkanecarboxylates 1 and N,Ndimethylphosphorylalkanecarboxamides 8 would preferentially react with organometallic reagents such as the titanium intermediates formed from organomagnesium halides and Ti(OiPr) 4 [or MeTi(OiPr) 3 ] to give C-phosphorylated cyclopropanols 7 and cyclopropylamines 12, respectively.Indeed, when methyl 3-(diphenylphosphinoyl)propionate was treated with two equivalents of ethylmagnesium bromide (6a) in the presence of titanium tetraisopropoxide (5) according to the original protocol 6a,b or its catalytic version, 6c the 1-(2'-diphenylphosphinoylethyl)cyclopropanol 7aa was isolated, albeit in low to moderate yield only (Scheme 1). The modified procedure, 11 in which the Grignard reagent is generated in situ, gave even lower yields. Scheme 1Better results were obtained, however, when the solution of ethylmagnesium bromide 6a (2.2 equiv.) was added to the mixture of the ester 1a (1.0 equiv.) and Ti(OiPr) 4 5 (1.0 equiv.) in THF at 0°C within 10 min, then the reaction mixture was allowed to warm up to room temperature and stirred for an additional 4 h. Using this same procedure, various 1-substituted and 1,2-disubstituted phosphorylalkyl-substituted cyclopropanols 7aa-7cc could be prepared from the correspondingly substituted esters 1a-c and Grignard reagents 6a-c in moderate to good yields (37-71%) ( Table 1). The reactio...