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In the presence of an amine, copper(1) chloride is an effective catalyst for the cross-dehycrocoupling of silanes with alkynes. The reactions proceed at useful rates above 100°C, but rates drop dramatically on going from lo to 2' to 3' organosilanes. Primary silanes, RSiH3 (R = Ph,n-hexyl), react in astepwisefashion with phenylacetylene to give the products RSiH3., (CCPh), (x = 1-3), each of which has been isolated and characterized. The secondary silanes RRiSiH2 (R = R' = Ph; R = Ph, R' = Me; R = n-Bu, R' = Me) also give mono-and diphenylethynyl products. The dehydrocoupling reaction has been applied to the synthesis of new polymers containing bothacetylene units and silicon atoms in the backbone. 1,3-Diethynylbenzene gives polymers of relatively high molecular weight (M, = lo4-lo5) with phenylsilane and phenylmethylsilane, but reactions of phenylmethyldiethynylsilane are too slow to give anything beyond low molecular weight oligomers.Key words: organosilanes, alkynes, dehydrocoupling, copper(1) chloride, polymers, catalysis.HUA QIN LIU et JOHN F. HARROD. Can. J. Chem. 68, 1 100 (1990).En prCsence d'une amine, le chlorure de cuivre(1) est un catalyseur efficace pour le dChydro-couplage croisC des silanes avec les alcynes. Les rCactions se produisent a des vitesses raisonnables lorsqu'on opere au-dessus de 100°C; toutefois, les vitesses diminuent d'une f a~o n dramatique lorsqu'on passe des organosilanes l o aux 2" et aux 3' . La rCaction des silanes primaires, RSiH3 (R = Ph, n-hexyle), avec le phCnylacCtylene se produit par Ctape pour donner les produits RSiH3, (CCPh), (x = 1-3); chacun de ces produits a CtC is016 et caractCrisC. Les silanes secondaires RR1SiH2 (R = R' = Ph; R = Ph, R' = Me; R = nBu, R' = Me) donnent aussi des produits mono-et di-phCnylCthynyles. On a appliquC la reaction de dthydro-couplage la synthbse de nouveaux polymeres dont la chaine fondamentale contient a la fois des unitCs acbtylbnes et des atomes de silicium. Avec le pEnylsilane et le phCnylmCthylsilane, le 1,3-diethynylbenzene fournit des polymkres de poids molCculaires relativement ClevCs (M, = lo4-lo5); toutefois, les rCactions du phCnylmCthyldiCthynylsilane sont tellement lentes que les seuls produits isolCs sont des oligombres de bas poids molCculaires.

To meet the demand of communication automation for outfield equipment test module, special embedded system was proposed by combing host computer control board and signal acquisition board, taking advantage of high data transmission efficiency on PC104 bus. Multichannel switch, signal recuperation circuit and Analog to Digital Converter (ADC) were controlled by FPGA logic on signal acquisition board. Signal data acquired were transmitted to host computer control board to display for user in real time. Application shows that the system was easy to operate. It performs well on real time ability and stability.