Stability explained

Compare electrostatic potential maps for planar and pyramidal forms of 2-methyl-2-propyl anion. For which is the negative charge more delocalized Is this the lower-energy structure For this case, does charge delocalization lead to stabilization Explain. 

Is product A1 or product A2 (resulting from the top reaction) lower in energy Why Can product stability explain why the lower reaction is selective Explain. 

Aeeording to your Lewis structure(s) and to the actual geometry of the molecule, is the bonding in planar corannulene fully delocalized (as in benzene), or are some CC bonds long and some short Do your results support the notion that planar corrannulene is resonance stabilized Explain. 

Topological charge stabilization explains the greater stability of indole (88), benzo[b]furan (89), and benzo[6]thiophene (90) compared to their positional isomers (91)-(93) when the largest 7r-charge densities at the 1,3-positions of the five-membered ring in the 10 7r-electron indenyl anion (94) are taken into account (77JA1692). Such an order of the relative stability is consistent with the RE values (Table X). 

Problem 8.6 Several factors can affect alkene stability. Explain why alkene A is more stable than alkene B even though both contain disubstituted carbon-carbon double bonds. 

Colorless, odorless gas. One of the heaviest known gases density approx 5 times that of air. mp —50,8. Sublimes at — 63.8. Crit temp 45.6. d (liq — 50.85) 1.88. Sparingly sol in water, somewhat more in alcohol. At 25° and 1 atm 0.297 ml SF4 dissolves in 1.0 ml of transformer oil. Thermodynamically unstable but kinetically stahle gas. This stability explained by symmetrical, octahedral structure of the molecule. Inert to nucleophilic attack. Does not attack glass. No fluorine exchange with HF. Stable to silent electrical discharge. Unchanged at 500. ... 

Problem 12.16. Show how carbocation stability explains Markovnikoffs rule in the addition of HCl to propene. 

Chlorine has two stable nuclides, C1 and Cl. In contrast, Cl is a radioactive nuclide that decays by beta emission, (a) What is the product of decay of Cl (b) Based on the empirical rules about nuclear stability, explain why the nucleus of Cl is less stable than either Cl or Cl. 

Rank order the following enolate anions in terms of their stability. Explain. 

While CH is stabilized by coordination to cyclobutadiene (see Exercise 42), the analogous structure in which a CH" is complexed to benzene, (CH)7% is not stabilized. Explain why this would be so. 

Do you expect the following dianion to exhibit aromatic stabilization Explain. 

Stability. Explain the following in terms of thermodynamic and kinetic... 

The order of carbocation stability explains Markovnikov s rule. Addition of the electrophile to the less substituted double bonded carbon atom gives the more stable carbocation. The formation of the more stable carbocation controls the product formed. 

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