Organic Chemistry Test 2 Review - HilinskiOxidation: loosing electrons (loosing H+) (Oxygen contest increases)Reduction: Gaining electrons (gaining H+) (Oxygen or bonds to it decrease)To calculate the average oxidation # you have to use what you already know:O = -2H = +1N = -3 in NH2X = -1 (x=OH, Br, Cl, F, I)Addition/elimination reactions (taking or adding water to a molecule) have no effect on the oxidation level.Carbon in its most oxidized form == CO2Carbon in its most reduced form == CH4 Sp3 > has 0 pi bondsSp2 > has 1 pi bondSp > has 2 pi bonds *Pi orbitals are parallel and they don’t hold molecules together, they can make bonds stronger though.*Single bonds are ALWAYs sigma bonds (there can only be one sigma bond between atoms the rest are pi bonds) Liquid nitrogen is diamagnetic (repelled in a magnetic field) and O2 is paramagneticStrain and ConfirmationsConfiguration = break bonds and reform them, rotations about a single bond Staggered (minimum in energy):Anti- 180 degrees between two main groups, most stable, lowest in energy. Gauche- 60 degrees, stability depends on what is interactingEclipsed (high in energy): atoms are on top of each otherA potential energy diagram is a graph of increasing potential energy vs. torsional angel in degrees. Angle strain- strain a molecule has because one or more of its bond angles deviates from the ideal angle (109.5)Torsional strain- destabilization that results when bonds on adjacent atoms are NOT staggeredVan der Waals strain- destabilization that results when atoms or groups on nonadjacent atoms are too close to one anotherCyclopropane has angle strain and torsional strain because the C-H bonds are all eclipsed. Cyclobutane relieves this strain by adopting a “puckered” form. The puckering decreases eclipsing interactions. Cyclopentaine has small angle train but the torsional strain is substantial because of the eclipsing hydrogens in its planar form. It relieves this strain by forming an envelope or half-chair confirmation. *Cyclohexane is free of angle and torsional strain because of its chair confirmation. A less stable form is the boat and less then the boat is the skew boat. The boats are all above the chair still. Torsional strainMethyl<Primary<Secondary<TertiaryThe most stable form of a chair will have the most strenuous alkyl group as equatorial. 1,3-diaxial strain results in a less stable confirmation. When drawing chairs:-allow axial bonds to alternate starting up from the head of the chair and down from the foot of the chair. -leave space in the back line of the chair for up-axial bonds that come up front. Stereoisomers= isomers that have their atoms bonded in the same order and have the same constitution but differ in the arrangements of atoms in space (usually cis- vs. trans-)NamingSpiro compounds-Start numbering from smallest ring to largest. Don’t start numbering at the Spiro carbon. Take the path that has the substituent at the lowest locant. Place numbers from smallest to largest after the spiro prefix. Bicyclic compounds- Start counting at either bridge head and start numbering towards largest bridge giving substituents the lowest locant number. It must ALWAYS have 3 number in brackets even if there is not bridge just put a 0. Anti- pointing away from lowest number bridgeSyn- pointing towards lowest number bridgeEndo- pointing away from highest number bridgeExo- pointing towards highest number bridgeHalides go in alphabetical order and give them the lowest umberAlkyl Halides: *Functional class: the alkyl group and halide are separate words. Starts counting the chain at the carbon that has the attached halide*Substitutive nomenclature: use the prefix of the halogen and add it to the name of the longest carbon chain (start counting on the Carbon that gives the substituted carbon the lowest number)Alcohols: named by placing the prefix of parent chain-locant # of OH group-ol suffix. (ex: hexa-7-ol) For functional naming: The chain is always numbered beginning with the carbon to which the –OH group is attachedFor Substitutive naming: identify the longest parent chain and replace the –e ending of the alkane with -ol*OH groups should take precedence over alkyl groups and halogens when determining which way to number the chain. ________________________________________________________________________________________________I.M. forces (from strongest to weakest> Hydrogen bonding, dipole-dipole, dispersionFor hydrogen bonding, the H must be bonded to a strongly electro(-) elementDimethylether has a lower bp. than ethanol.As molecular weight increases so does boiling pointAs I.M. force strength increases so does bp.Molecules with hydrogen bonding have higher bp. then molecules with just dispersion forces.*The bp. of chlorinated derivatives of methane increasing with the number of Cl atoms because the induced-dipole/induced-dipole attractive forces increase with each replacement of hydrogen. *Because of the low polarizability of Fluorine, its bp. does not increase as more fluorines are added. CH2 is methyleneCH is Methine*Perfluro- = each H was replaced with a Fluoride “F” is not very polarizable (e- cloud is like a gold ball)“I” is very polarizable meaning we can deform its e- cloud (squishy like a nerf-ball)Teflon is polytetrafouraethene C2F4PHYSICAL PROPERTIESSolubility in Water*All alkyl halides are insoluble in water Anything greater then or equal to C5H12O is not soluble in water. The OH group is hydrophilic/lipophobicThe Carbon skeleton is lipophilic/hydrophobic 1-pentanol is more soluble then 1-hexanolDensityRF & RCl are less dense then water so they floatRBr & RI are denser then water so they sink ROH’s are less dense then water so they float * If there is more then 1 halogen then it is more dense then waterReaction MechanismsThe preparation of Alkyl Halides from Alcohols and Hydrogen Halides Sn1The reactions will either start with an alkane or an alcohol to make the alkyl halide. Alcohol + Hydrogen Halide >> Alkyl Halide + WaterOrder of reactivity: HI> HB > HCl >> HFPrimary (least reactive)<Secondary<Tertiary (most reactive)Tertiary alcohols are converted to alkyl chlorides VERY fast when they are mixed with HClSecondary and Primary don’t react with HC; as fast so they use HBrThe reaction of an alcohol with a hydrogen halide is a substitution. A halogen replaces a hydroxyl group on a carbon. Step 1: A proton from the acid breaks off and goes to the alcohol to form an alkyloxonium