Ethers Hybrid orbital

In dimethyl ether, the oxygen atom is sp3 hybridized. In creating two single bonds, each bond is formed by the overlap of one of its sp3 hybrid orbitals with the sp3 hybrid orbital on the adjacent carbon atom. Each of the remaining two hybrid orbitals on the oxygen atom contain a lone pair of electrons. The resulting molecule is polar. The intermolecular forces found operating between molecules of dimethyl ether are therefore dipole-dipole interactions and London forces. 

Hunsdiecker reaction, 341 Hybridization, 17 Hybrid orbital number, 17, 18, 32 Hybrid, resonance, 24 Hydration of cyclohexane derivatives, 191 Hydrazine, 4 Hydride shift, 93 Hydroboration, 95 Hydroboration-oxidation, 258, 270 Hydrocarbons, cyclic, 162 unsaturated, 87 Hydrogenation of alkenes, 57 Hydrogen bond, 22 Hydroperoxides in ethers, 284 Hydroquinone, 430 Hydroxy acids, 344... 

As a result of an analysis of numerous data on the direction of hydrolysis reactions of ethers and amides which proceed via formation of the type XXVII intermediates, a simple phenomenological theory was evolved of stereoelectronic control of fragmentation of tetrahedral intermediates [120, 121]. This theory rests on the classical notion of the hybrid orbitals of electron lone pairs (ELP) of heteroatoms. 

CCSD(T) = coupled cluster configuration interaction including all singly and doubly excited configurations with perturbative inclusion of triples CISD = configuration interaction all singly and doubly excited configurations included DME = dimethyl ether NHO = natural hybrid orbital PDME = proto-nated dimethyl ether. 

In both alcohols and ethers, the C—O O bond is formed by the overlap of two sp hybrid orbitals, one on the oxygen atom and one on the carbon atom. The C—O bond is slightly shorter, 142 pm, than the C—C bond, 143 pm. The lone pair electrons in both alcohols and ethers are directed toward the corners of a tetrahedron. 

Similarly, in planar bonding (e.g., H2O or related alcohols and ethers), hybridization can only involve the two p orbitals (e.g., P Py) that he in the plane of bonding. Hybridization of oxygen s, p, Py orbitals therefore results in three orthonormal hybrids in the bonding x-y plane, one of which becomes the in-plane (as seen, e.g., in NBO 8 of Fig. 4.2 for CH3OH), while the remaining unused p orbital becomes the out-of-plane (e.g., NBO 9... 

A qualitatively similar dependence of ADh on boron orbital hybridization is noted in boron hydrides (104). -1bh = 81 cps for BHr where boron is tetrahedral while ABH = 136 cps for borazole where boron presumably is sp2. A ijh for BH3 adducts with ethers, amines, and phosphines range between 90 and 103 cps and for these compounds boron quadrupole coupling constants have been interpreted (22) in terms of a boron hybridization intermediate between sp2 and sp2. However, the simple dependence of... 

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