A new type of track detector, scintillating track image camera (SCITIC) has been developed. Scintillating track images of particles in a scintillator are focused by an optical lens system on a photocathode on image intesifier tube (IIT). The image signals are amplified by an IIT-cascade and stored by a CCD camera. The performance of the detector has been tested with cosmic-ray muons and with pion-and proton-beams from the KEK 12-GeV proton synchrotron. Data of the test experiments have shown promising features of SCITIC as a triggerable track detector with a variety of possibilities.
Addition of alcohols to bis(chloromethyl)phosphinoyl isoeyanate, as well as the re.action of bis(chloromethyl)phosphinoyl chloride with urethanes or their silylated derivatives, gave the corresponding phosphorylated carbamates which undergo cyclization into 1,3,4-oxazaphospholines under the action of Et3N.Key words: bis(chloromethyl)phosphinoyl chloride(isocyanate), phosphorylated carbamates, heterocyciization, 1,3,4-oxazaphospholines.At present, we are developing methods for the synthesis of polyheterophosphacyclanes with an endocyclic P--C bond. These are based on intramolecular transformations of polyfunctional derivatives of the four-coordinate phosphorus atom. 1 In particular, various saturated and unsaturated phosphacyclanes with the P--C bond can be obtained by combination ofa chloromethyl group and urea (thiourea, acylamide, etc.) fragments in a molecule. Functionalized chloromethylphosphonates (-phosphinates) cart be synthesized by addition of amines, thiols, hydrazines, phosphines, and other protonic nucleophiles to (thio)phosphonoyl(phosphinoyl) iso(thio)-cyanates. 1-5 We undertook synthesis of phosphorylated carbamates bearing the chloromethyl groups at the phosphorus atom and attempted to perform their cyclization.We developed three methods for the synthesis of the target products. Bis(chloromethyl)phosphinoyl isocyanate (1) easily adds alcohols to give phosphorylated carbamates (2, 3).The structures and compositions of compounds 2 and 3 were confirmed by data from NMR and IR spectroscopy and elemental analysis. Taking into account the data obtained by us earlier, * we attempted to synthesize compounds 2 and 3 by phosphorylating silylated carbamates. The reaction of bis(chloromethyl)-phosphinoyl chloride (4) with ethyl N-trimethylsilylcarbamates 7 (5) easily proceeds with the elimination of chlorotrimethylsilane to give product 3. In addition, compound 3 cart be obtained by phosphorylation of ethyl carbamate (6) with chloride 4 in the absence of a base.
+ H2NCOOEt= 3
6In the presence of tfiethylamine, carbamates 2 and 3 easily split off hydrogen chloride to transform into the corresponding 1,3,4-thiazaphospholines (7, 8).
(3)The structures and compositions of compounds 7 and 8 were confirmed by data from NMR and IR spectroscopy and elemental analysis. Note that the protons of the endo-and exocyclic methylene groups manifest themselves as one doublet in the IH NMR spectra.
Experimental31p NMR spectra were recorded on a Bruker MSL-400 spectrometer (161.97 MHz) with 85% H3PO 4 as the external
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