1066-27-9

Upstream product

• 169128-92-1 1,1,1-Trimethyl-2-vinyldisilan 
• 67616-99-3 silacyclopropenylidene 
• 684-24-2 hexa-Si-chloro-Si,Si'-(2-chloro-ethene-1,1-diyl)-bis-silane 
• 74-86-2 acetylene 

Relevant academic research and scientific papers

COMPOUNDS USEFUL AS ANTIPROLIFERATIVE AGENTS AND GARFT INHIBITORS

The invention relates to compounds, such as compound (1) in equilibrium with its 4-hydroxy tautomer, and its pharmaceutically acceptable salts. Such compounds are useful as inhibitors of glycinamide ribonucleotide formyl transferase (GARFT) or as antiproliferative agents. The invention also pertains to pharmaceutical compositions and methods employing such compounds as GARFT inhibitors or antiproliferative agents. The invention also relates to compounds useful as intermediates for preparing such compounds.

Reaction of silicon atoms with acetylene and ethylene: Generation and matrix-spectroscopic identification of C2H2Si and C2H4Si isomers

Evaporation of silicon and consecutive cocondensation of the generated atoms with acetylene or ethylene in an argon matrix turnes out to be a new access to C2H2Si and C2H4Si isomers, respectively. In both cases the silicon atoms rather add to the π system than insert into C-H bonds, leading to cyclic silylenes as primary reaction products. In the Si/ acetylene system the primary product is silacyclopropenylidene (2), which shows the already known photochemical interconversion into additional C2H2Si species. On the other hand, cocondensation of silicon atoms with ethylene and subsequent irradiation lead to the matrixisolation of three new C2H4Si isomers [apart from the known silacyclopropene (7) and silylacetylene (8)], namely silacyclopropylidene (10), s-trans-vinylsilylene (11), and the unsubstituted 1-silaallene (13), These species can be identified by comparison of their experimental IR spectra and those obtained by ab initio calculations. In a second reaction path, SiH2, which is formed as a byproduct from atomic silicon and hydrogen impurities, adds to the π system of acetylene, yielding silacyclopropene (7). Silacyclopropane (16), the analogous product of the reaction of SiH2 with ethylene, could not be observed.

Processes for preparing antiproliferative garft-inhibiting compounds

The invention generally relates to compounds of the formula I, which are in equilibrium with their 4-hydroxy tautomers, and their pharmaceutically acceptable salts: STR1 where n is 0 to 2; A is S, CH2, O, NH or Se, and when n is 0, A is not CH2, and when n is 1, A is not CH2 or NH; X is a substituted or unsubstituted C1 -C3 alkyl, C2 -C3 alkenyl, C2 -C3 alkynyl or amino, or sulfur or oxygen; Ar is a substituted or unsubstituted monocyclic carbocycle or heterocycle, or fused or nonfused polycyclic carbocycle or heterocycle; and R1 and R2 are hydrogen or a moiety that forms together with the attached CO2 a readily hydrolyzable ester group. These compounds and their salts are useful as inhibitors of GARFT or as antiproliferative agents. The invention also pertains to pharmaceutical compositions and methods employing such compounds as GARFT inhibitors or antiproliferative agents. The invention also relates to compounds useful as intermediates for preparing such compounds, and to their synthesis.

Silacyclopropen: Bildung durch Hochvakuum-Blitzpyrolyse und matrixspektroskopische Identifizierung

Stichworte: Blitzpyrolyse.Gespannte Ringe.Photochemie.Siliciumverbindungen

Synthesis and Molecular Structure of Silylated Ethenes and Acetylenes

Disilylacetylene (1) has been obtained from LiAlH4 reduction of bis(trichlorosilyl)acetylene (2) and bisacetylene (4).The catalytic hydrosilylation of 2 with HSiCl3 affords tris(trichlorosilyl)ethene (5) and 1,1,2-tris(trichlorosilyl)ethane (6).The synthesis of 6, trans-bis(trichlorosilyl)ethene (8) and 1,1-bis(trichlorosilyl)ethene (9) has been accomplished by hydrosilylation of trichlorosilylacetylene (7) which was synthesized by the reaction of trichloro(trifluoromethylsulfonyloxy)silane with sodium acetylide.Reductive elimination of halogen from 1,1,1,2-tetrachloro-bis(trichlorosilyl)ethane (10) and 1,2-dibromo-1,1-bis(trichlorosilyl)ethane (13) gave the corresponding ethenes 1,1-dichloro-bis-(trichlorosilyl)ethene (11), trichloro-trichlorosilylethene (12), 1,1-bis(trichlorosilyl)ethene (9) and 1-chloro-2,2-bis(trichlorosilyl)ethene (14).Tetrakis(trichlorosilyl)ethene (15) has been obtained in a three step synthesis starting from chloromethyl-trichlorosilane or dichloromethyl-trichlorosilane.By LiAlH4 reduction of trichlorosilylethenes under various reaction conditions, the silylethenes trans-dichloro-di(silyl)ethene (16), 1,1-dichloro-di(silyl)ethene (17), trichloro-silylethene (18), 1-bromo-1-silylethene (19), trans-di(silyl)ethene (20), 1-chloro-2,2-di(silyl)ethene (21), tri(silyl)ethene (22), and 1,1,2-tri(silyl)ethane (23) could be generated.Silylethyne and silyl-chloroethyne were identified as side products.The crystal and molecular structures of 2, 5 and 15 have been determined by single crystal X-ray diffraction. 2 and 5 crystallize from the melt in the monoclinic space groups Cc and P21/n, respectively. 15 has been crystallized by sublimation (orthorhombic, space group Pbca). 5 and 15 feature strongly distorted ethene skeletons with a double bond twist of 28.1 deg in 15. - Keywords: Silanes, Trichlorosilanes, Polysilylethenes, Carbon Halogenated Silylolefines

Pressure-dependent Isotope Effect in the Reaction of Silylene (SiH2, 1A1) with Acetylene and Acetylene

Direct, time resolved measurements of absolute rate constants for reaction of SiH2(1A1) with C2H2 and C2D2 have revealed a pressure (and temperature) dependent isotope effect characteristic of an association process yielding an intermediate (silirene) which undergoes, amongst other reactions, a degenerate isotopic scrambling process.