Diethyl ether planar

Chlorohydridobis(tricyclohexylphosphine)nickel is a yellow-brown solid. It is thermally stable at ambient temperature but reacts with air. It is very soluble in benzene, tetrahydrofuran, and dichloromethane and is soluble in diethyl ether and petroleum ether. Carbon tetrachloride, carbon disulfide, and chloroform decompose the complex. The infrared spectrum shows a sharp v(Ni—H) band at 1916 cm-1 (KBr disk and Nujol mull). The high-field H nmr spectrum in benzene solution has a triplet (1 2 1) at t34.6 (TMS) with JpH 73.5 Hz. The splitting is caused by the coupling of the hydride proton with two equivalent 31P nuclei. This is consistent with a trans square-planar configuration. 

This square planar nickel(ll) complex is stable in air in the solid state, but solutions of the complex react in air to produce oxidation products of unknown composition. For this reason, manipulations of the complex are best performed in an inert atmosphere. The complex is a nonelectrolyte and is soluble in most common organic solvents, including diethyl ether, but not in water. The infrared spectrum of the complex contains an intense broad band in the double-bond region centered at 1610 cm. The electronic spectrum of a solution of the compound in toluene contains several bands 17.9 (e = 107), 23.0 (e 1600), 24.5 (e 4600), 25.9 (e 2700), and 29.4 kK (e 5500). The PMR spectrum of the complex in CDCI3 contains four bands as expected singlet methyl at 5 1.88, methylene at 6 3.13, vinyl doublet at 6 4.51, and a second vinyl doublet at 5 6.63. The vinyl protons of the charged chelate ring are coupled, J = 3 Hz. 

Treatment of the dichloro species (120) with 3,4-dilithio-2,5-dimethyl-2,4-hexadiene (121) in diethyl ether afforded the l-sila-3-boracyclopentane (122) in 41% yield (Equation (24)) <91ZN(B)l 127>. This heterocycle could be distilled in vacuo and recrystallized from pentane at —20°C. The H NMR spectrum of (122) exhibited two signals ( = 0.43 and 0.50) for the methyl groups (axial and equatorial) on silicon, indicating a non-planar ring (which was confirmed by an x-ray structure). 

Di- -alkyl ethers The effective conformation of diethyl ether (in CT, 25°) has the terminal C—Me bonds rotated ca. 24° from a flat zig-zag structure so that they are trans with respect to the C—0—C plane. A non-planar conformation for di-n-propyl ether, compatible with the observed oo(, 2), can be specified with higher ethers the possibilities of internal rotations make this difficult Aroney et al., 1962c... 

Since ot-nitroso-p-naphthol (11 pK = 7.70) and p-nitroso-a-naphthol (p/C 7.22) are weaker acids than nitrosophenylhydroxylamine (16 p/C=4.15), complex formation and solvent extraction require more alkaline solutions. Tris complexes of Fe or Co are formally uncharged octahedral species extractable into light petroleum like the uncharged square planar complex of Pd . On the other hand the bis complexes of Fe , Ni and Co require two water molecules to complete their coordination sphere and though extractable into diethyl ether are insoluble in the non-polar ligroin. 

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