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-positive alpha-carbon
-acidic beta-carbon
-elevation in BP from alkane due to dipole
-BP not up to alcohol due to no hydrogen bonding
-aldehydes more reactive than ketones. Why?

-hydrogen bonding (# hydroxyl groups)
-high boiling points
-weakly acidic (pKa = 10phenol to 16water)
-6-carbon rule = alcohols with C-chains > 6 are no longer soluble

1. Huckel's Rule (4n+2)
2. Planar and cyclic
3. Every atom delocalized

Trans alkenes have higher melting points (symmetrical) and lower boiling points (less likely to be polar).

SP3 carbons donate electrons to SP2 carbons - orbitals more s character, closer to nucleus, more stable.

1. KMnO
     - mild conditions (vicinal diols)
     - extreme conditions (carboxylic acids)

2. Ozonolysis
     - mild conditions, reducing Zn/water environment (ketones/aldehydes)
     - extreme conditions, oxidizing environment

3. NaBH or LiAlH

4. Peroxyacetic acids = CHCOH or MCPBA (epoxide formation)

5. Hydroboration (NaBH, peroxide)

-bulky, stronger base
   (NOT -CN or -I or even -OH, but -OR)
-substrate steric hindrance
   (why? hydrogen removal rather than )
-HEAT

Key Points
bulky base = E2
heat = E2
3*C substrate = E2

Find the amount of product formed per hydrogen and compare.

Related species that are similar in energy are also similar in structure. The structure of the transition state resembles the structure of the closest stable species.

-transition state for endothermic rxns resembles the product, exothermic the reactant.
-bromination transition state is closest to product. Thus reactivity very closely related to end-product stability (i.e. stability=speed).

*chain length; increase
   -bioling point
   -melting point
   -density

*branching; decrease
   -boiling point
   -density

*melting point and branching - determined by how symmetrical the molcule is; packing density. Easier to stack, more dense, higher melting point.

1. Basicity of Nu
       RO- > HO- > RCO > ROH > HO
2. Polarizability (size) of Nu
       CN- > I- > RO- > HO- > Br-
3. Solvent
      -protic = solvate the leaving group.
      -polar = solvate the intermediate.
4. Leaving group (base weakness)
5. Substrate (charge delocalization)

Relative = experimentally determined, x-ray crystallography; always reversed in SN2 reactions (D/L; +/-).

Absolute = determined by priority group orientations; not necessarily reversed in SN2 reactions (R/S).

-good leaving group
-stable substrate, bulky Nu.
-favored in polar, protic solvents
-two steps (two transition states)
-rate=k[RX] ; first order kinetics
-racemic products
-rate limiting step is the first step = formation of the carbocation.

1. Slower reaction
2. Transition state more dependent on product stability (endothermic)

Intermediate = stable, relative minimum, stable species.
Transition state = theoretical, unstable, relative maximum, for mechanism solely.

-Nu > leaving group
-favored in aprotic POLAR solvents
-r=k[Nu][RX] ; second-order kinetics
-reverse relative configuration
-no steric hindrance in substrate, small Nu.
-trigonal bipyramidal transition state (sp)

Non-superimposable mirror images.

Same physical properties except rotation of polarized light
Same chemical properties except with chiral molecules

Similar - Large in physical and chemical properties.

Same molecular weight and molecular formula.
Different atomic connectivity.
Different physical properties.
Different chemical properties.

*Number of isomers per CH formula.

Same atomic connectivity, but different arrangement in space.

1. Conformational
2. Geometric
3. Enantiomers
4. Diastereomers
5. Meso compounds

Do not need bond breaking to convert from one to another.
i.e. rotation about a bond.

Same physical and chemical properties.

Require bond breaking to interconvert.

1. Geometric
2. Optical

Stereoisomerism at a double bond or cycloalkane.
i.e. cis or trans, (Z) or (E)

Different properties when difference in net polarities

Configurational isomerism involving single bonds.

1. Diastereomers
2. Enantiomers
3. Meso compounds

- more substituted bond product favored
- trans isomer favored
- anti hydrogen removed by base

* losing hydrogens
* gaining double bond
* gaining oxygen

* Lewis acid = e acceptor.
* Lewis base = e donator (benevolent).

the goal is to produce the most stable carbocation in alkyl halide addition to double bonds.
addition of the halogen to the more substituted carbon in the double bond.

* higher boiling points than alkenes
* more polarized than alkenes
* internal alkynes BP > terminal alkynes BP
* terminal alkynes fairly acidic (PKA~25) due to high s character (50%), stabilize negative charge.