Air stable

The most hindered of all presently known hydroborating agents is possibly dimesitylborane, an air-stable white soHd, slightly soluble in tetrahydrofuran, the best etheral solvent. It is commercially available or can be prepared according to the following reaction (117) ... 

Air-Stable boron-containing polymers can be prepared by the reaction of dicyano compounds with the / fZ-butylborane—trimethyl amine complex (449). 

X 10 J/T (5.71 //g) at room temperature. It is air stable at 25°C, but is slowly converted to Fe202 and bromine at 310°C. The light yellow to brown hydroscopic sohd is soluble ia water, alcohol, ether, and acetonitrile. Iron(II) bromide forms adducts with a wide range of donor molecules. Pale green nona-, hexa-, tetra-, and dihydrate species can be crystallized from aqueous solutions at different temperatures. A hydrate of variable water content,... 

The reaction of a mixture of 1,5,9-cyclododecatriene (CDT), nickel acetylacetonate [3264-82-2], and diethylethoxyalurninum in ether gives red, air-sensitive, needle crystals of (CDT)Ni [12126-69-1] (66). Crystallographic studies indicate that the nickel atom is located in the center of the 12-membered ring of (CDT)Ni (104). The latter reacts readily with 1,5-cyclooctadiene (COD) to yield bis(COD) nickel [1295-35-8] which has yellow crystals and is fairly air stable, mp 142°C (dec) (20). Bis(COD)nickel also can be prepared by the reaction of 1,5-COD, triethylaluminum, and nickel acetylacetonate. 

A rather air-stable titanocycle [76933-94-3 76933-97-6] has been prepared in meso form only (281) ... 

Related examples of silicon-containing titanocycles have also been prepared (282). These compounds are air-stable and not decomposed by methanol. When CpCpWiClOAr reacts with Grignard reagents, the aryloxy group is replaced by R, not by Cl (283). Compounds of the formula (Cp2TiR)20 prepared from (CP2TiCl)20 + RLi, where Ris CH, C2H, CgH, y)-tolyl, CgH CM2, or CH2=CH, are thermally stable and quite stable to air (283,284). 

Sodium Tetrahydroborate, Na[BH ]. This air-stable white powder, commonly referred to as sodium borohydride, is the most widely commercialized boron hydride material. It is used in a variety of industrial processes including bleaching of paper pulp and clays, preparation and purification of organic chemicals and pharmaceuticals, textile dye reduction, recovery of valuable metals, wastewater treatment, and production of dithionite compounds. Sodium borohydride is produced in the United States by Morton International, Inc., the Alfa Division of Johnson Matthey, Inc., and Covan Limited, with Morton International supplying about 75% of market. More than six million pounds of this material suppHed as powder, pellets, and aqueous solution, were produced in 1990. 

Copper Oxides. Coppet(I) oxide [1317-39-17 is a cubic or octahedral naturally occurring mineral known as cuprite [1308-76-5]. It is ted or reddish brown in color. Commercially prepared coppet(I) oxides vary in color from yellow to orange to ted to purple as particle size increases. Usually coppet(I) oxide is prepared by pytometaHutgical methods. It is prepared by heating copper powder in air above 1030°C or by blending coppet(II) oxide with carbon and heating to 750°C in an inert atmosphere. A particularly air-stable coppet(I) oxide is produced when a stoichiometric blend of coppet(II) oxide and copper powder ate heated to 800—900°C in the absence of oxygen. Lower temperatures can be used if ammonia is added to the gas stream (27-29). 

The submitters used dich1orobis(n -cyclopentadienyl)zirconium available from Aldrich Chemical Company. This chemical is sufficiently air-stable to be handled in air. 

The submitters state that the copper(I) triflate is quite air stable In solution In the presence of the allyllc alcohol. 

The thiotrithiazyl cation in [S4N3]C1 was one of the first S-N heterocycles to be prepared and structurally characterized. It is obtained as a reasonably air-stable, yellow solid by the reaction of S4N4 or [SsNaClJCl with S2CI2 in CCI4 (Eq. 5.12)." ... 

The 1,5-isomers 13.3 (E = S) are colourless, air-stable solids. They are prepared by the cyclocondensation reaction of R2PN2(SiMe3)3 with sulfur dichloride or thionyl chloride. A similar cyclocondensation process, using a mixture of SeCU and Sc2Cl2 as a source of selenium, produces a mixture of the isomers 13.2 and 13.3 (E = Se, R = Ph). The structures of 13.3 (E = S, R = alkyl, aryl) are folded eight-membered rings with a cross-ring S S distance of ca. 2.50 This structural... 

The unexpectedly complex product was isolated as an almost colourless air-stable powder, and a single-crystal X-ray analysis showed that it had the molecular adamantane-like structure (5). This is very similar to the structure of the iso-electronic compound P4O10 (p. 504). 

In contrast to the numerous complexes of NO which have been prepared and characterized, complexes of the thionitrosyl ligand (NS) are virtually unknown, as is the free ligand itself. The first such complex [Mo(NS)(S2CNMc2)3] was obtained as orange-red air-stable crystals by treating [MoN(S2CNMe2>3] with sulfur in... 

Thermal decomposition of [N(PPh3)2]" -[S4N5] in MeCN yields sequentially the corresponding salts of S3N3 and S4N (50% yield). An X-ray crystallographic analysis of the dark-blue air-stable product [N(PPh3)2] [S4N] revealed the presence of the unique acyclic anion [SSNSS] whose structure is in Fig. 15.42c. The anion is planar with cis-trans configuration. 

The paramagnetic impurity which invariably accompanies Wilkinson s catalyst has proved difficult to identify. It is probably the air-stable, green, irans- (RhCl(CO)(PPh3)2j- see K. R. Dunbar and S. C Harfner, Innrg. Chem. 31, 36"76-9 (1992),... 

However, uranocene can be made more air-stable by use of sufficiently bulky substituents, and 1,3,5,7-tetraphenylcyclo-octatetraene yields the completely air-stable [U( -CgH4Ph4)2], in which the parallel ligands are virtually eclipsed but the phenyl substituents staggered and rotated on average 42° out of the Cg ring plane (Fig. 31.10). 

A4,5,2,4-Benzotrithiadiazepineis a yellow air-stable solid.394 The X-ray structure384 shows that it is planar, but although it can be considered to be an aromatic 147t-systcm there is some bond-length alternation within the rings compared with the monocyclic trithiadiazepine. 

Polybenzyls polyphenethyls Parylenes (poly-p-xylylene) Fusible, soluble, and stable at 400°C (752°F) low molecular weight. Melt above 520°C (968°F) insoluble capable of forming films poor thermal stability in air stable to 400-525° C (752-977°F) in inert atmosphere. 

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