Bonds to Chlorine

Bonds to Chlorine.— The reaction between PCI3 and an excess of methanol in the cold has been reinvestigated, to show that more than two moles of HCl are liberated dimethyl ether can also be detected as a product, but there is no evidence for the phosphonate MePO(OMe)2. A mechanism based on the dealkylation of the assumed intermediate P(OMe)3 has been postulated to account for these observations. Eutectics only are found in the PCl3-TeCl4 and AsCli-TeCU systems, but with POCI3 an incongruently melting 1 1 adduct is formed.Modification of silica surfaces to incorporate Cr -P -0 layers can be achieved by successive treatment with chromyl chloride and phosphorus trichloride. 

As part of a general study of reactions of MePCU or MeP(OMe)2 to give oligomeric condensation products, exchange in the MePCl2-Me M(OMe)4 systems (M = Si, n-2 or 3 M = Ge, n = 2) has been investigated. Chloride-methoxide exchange is rapid at room temperature, but this is followed by condensation of the mixed species, as shown in equation (45). In the reverse  

The preferred conformation for both ethyl- and isopropyl-dichlorophosphines is that in which a methyl group and the lone pair are trans to each other, according to low-temperature n.m.r. data, and there is evidence for the formation of 

Phase studies point to the formation of high-melting 1 1 adducts in the PCI5-AICI3 and PCls-FeCl.3 systems, while Raman data for the PCls,UCl5 adduct have been interpreted in terms of the ionic structure Further 

Substitution of the chlorine atoms in POCI3 by biphenyl-2-ol and o-cyclo-hexylphenol and in chloromethylphosphonic dichloride, CICH2POCI2, by primary aliphatic amines has been investigated. Methylphosphonic dichloride can now be obtained in good yield by a one-step process, i.e. slow addition of MeP(0)(0Me)2 to an excess of refluxing thionyl chloride, and, while the technique can be extended to the ethyl derivative, pure BuP(0)Cl2 could not be prepared. 

Dillon, T. C. Waddington, and D. Younger, Inorg. Nuclear Chem. Letters, 1974, 10, 111. 

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If the carbon atom bonded to chlorine is itself attached to further carbon atoms, the effect can be transmitted further ... 

Strongly nucleophilic lithium aluminum hydride and sodium borohydride in diglyme replace vinylic halogens including fluorine [521, 555], sometimes under surprisingly gentle conditions [52/]. Because the carbon atom linked to fluorine is more electrophilic than that bonded to chlorine, fluorine in 1-... 

Fig. 14 Natural abundance carbon-13 spectrum of 1 (50 MHz) with expansion where necessary to show doublet structure. The assignments are as follows (from left to right), aromatic C bonded to oxygen (doublet) aromatic C bonded to chlorine (singlet) aromatic CH (singlet) methine (doublet) CDC13 OCH2 (doublet) CH3 (doublet). Multiplet splittings are due to coupling with phosphorus and are (except for Jpc) small...

Exercise 29-14 The terminal carbon of the epoxide ring of epichlorohydrin generally is quite a bit more reactive toward nucleophilic agents than is the carbon bonded to chlorine. Work out a mechanism for the following reaction that takes account of this fact (review Section 15-11D) ... 

Direct calculation shows that for a mixture of 22% CO, 78% air, 1.8% H20, the introduction of 1% CC14 even raises the combustion temperature from 2079 to 2092°K (the difference, however, is close to the calculation error). In the combustion products at the theoretical temperature of 2080° K, once complete chemical equilibrium has been established, more than 90% of the hydrogen turns out to be bonded to chlorine in the form of HC1. Apparently it is precisely in the hydrogen bonding, necessary for combustion of carbon monoxide, that the flegmatizing role of CC14 lies. The action of CC14... 

In Gordy s approach the ionic character of a single bond to chlorine equals one-half of the difference in electronegativities of the chlorine, 3.16, and the atom to which it is bonded. Thus the NQR frequency of this chlorine atom is a strong function of the Pauling electronegativity, Xp, of the atom M bonded to chlorine ... 

It has not been possible yet to prepare chalcogen(VI) hexahalides with the heavy halogens. The chemistry of hexavalent chalcogen compounds with bonds to chlorine, bromine, and iodine is essentially restricted to the mixed-ligand molecules SCIF5, SBrFs, SeClFs, TeClFs, TeBrFs, and derivatives thereof. By far the largest proportion of published papers refers to the sulfur compounds. 

This procedure creates two unpaired electrons which could theoretically bond to chlorine in two different bonds, one using a p orbital, the other a s orbital. However, it is an established fact the two bonds in beryllium are equivalent. Consequently, the orbitals must be combined, The scheme below shows the combination of one s and one p orbitals to produce the mixed (hybrid) orbitals ... 

The two arrows show (1) movement of a pair of electrons from oxygen to carbon to form the new C—O bond and (2) movement of a pair of electrons from the C—Cl bond to chlorine to form the chloride ion. Mechanism arrows depict the movement of pairs of electrons, not the movement of atoms. This is a logical result of the fact that chemical reactions are due to changes in bonds, and bonds are made out of electrons. Practice using electron pushing in mechanisms as frequently as you can so that you can get used to the technique. Note that proper use of electron-pair arrows automatically results in the correct Lewis structures for the products of a reaction, including charges, if any. An example of its application to an even simpler reaction, the reaction of an acid and a base, is shown below. 

Bonds to Chlorine and Iodine.— The first band in the photoelectron spectrum of NSCl has been assigned to an ionization process involving the 16a (Detonation velocities of N3CI have n studied. ... 

The other common elements suitable as chain caps are fluorine and chlorine, but they are worse than hydrogen. Carbon, silicon, and phosphorus form extronely strong bonds to fluorine— so strong that silicon-silicon and phosphorus-phosphorus bonds cannot compete. And, except for carbon, bonds to chlorine cannot compete with bonds to oxygai. 

Sample Solution (a) ferf-Butoxy radical adds to the CH2 group of vinyl chloride. The free radical formed in this process has its unpaired electron on the carbon bonded to chlorine. 

When carbon is bonded to chlorine, for example, the bonding electrons are attracted more strongly to the chlorine atom. The carbon atom bears a small partial positive charge, and the chlorine atom bears an equal amount of negative charge. Figure I -6 shows the polar carbon-chlorine bond in chloromethane. We symbolize the bond polarity by an... 

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