orgchem

• The basic IUPAC organic compound naming rules are Step 1:  Identify parent chain => longest carbon chain. In case of tie most substituted wins Step 2:  Identify the suffix name / highest priority functional group Step 3:  Identify the #1 carbon a.     Linear chain: #1 is end carbon closest to highest priority functional group b.     In case of tie: #1 is end carbon giving lowest numbers to any substituted carbons c.      Rings: #1 is carbon of highest substitution ascending in direction giving lowest numbers to highest priority fnal group Step 4:  Name the substituents with their prefixes a.     If more than one of the same type use di- tri- tetra- etc prefixes b.     Apply their position numbers c.      Order them in alphabetical order ignoring hyphenated prefixes but honor nonhyphenated prefixes like neo iso cyclo Step 5:  Assemble the name: (numbers prefixes) | parent chain length/name | suffix
• A substituent is any atom or group of atoms that replaces one or more H atoms on the parent chain. “Most substituted” and “least substituted” refer to the number of parent chain H atoms that are replaced by something else (including main chain double and triple bonds).
• Common alkyl groups: what are structures of t-butyl, neopentyl, isopropyl, sec-butyl, isobutyl?:t-butyl:       neopentyl  isopropyl     sec-butyl     isobutyl       "
• Name these alkyl groups:t-butyl:       neopentyl  isopropyl     sec-butyl     isobutyl       "
• Names of first 12 alkanes are methane ethane propane butane pentane hexane heptane octane nonane decane undecane and dodecane.
• Halogens are common substituents on alkanes. Alkyl halides are indicated by a prefix: fluoro– chloro– bromo– or iodo–.
• Double / triple bonds are: named like a substituent; numbered by the lower-numbered carbon in the bond position of the number can be either e.g.  2-butene or but-2-ene either is correct
• Aldehydes and ketones have an in-chain carbonyl carbon. Aldehydes have it at the end of a chain R-CHO; ketones have it in the interior R-CO-R.
• Because aldehydes have the carbonyl carbon at the end of a chain and are a high priority functional group the carbonyl carbon is usually #1.
• Methanal ethanal and propanal are referred to almost exclusively by their common names formaldehyde acetaldehyde and propionaldehyde rather than their IUPAC names.
• Ketones contain a carbonyl carbon located somewhere in the middle of the carbon chain.
• Carboxylic acids contain a carbonyl group (C=O) and a hydroxyl group (–OH) located at a terminal carbon.
• Carboxylic acids have three derivatives each obtained by replacing the OH with another substituent. These derivatives are esters amides and anhydrides.
• An ester is a carboxylic acid derivative in which the OH of the acid is replaced by -OR.
• An amide is a carboxylic acid derivative in which the OH of the acid is replaced by -NRR.
• An anhydride is a carboxylic acid derivative in which the OH of the acid is replaced by the OH of another carboxylic acid with a water removed to give O=C-O-C=O.
• This structure is an example of an amide "
• This structure is an example of an anhydride "
• These structures are examples of what? esters Name them:  ethyl propanoate  propyl methanoate  methyl butanoate  propyl ethanoate " "Esters Esters are common carboxylic acid derivatives. In these compounds the hydroxyl group (–OH) is replaced with an alkoxy group (–OR where R is a hydrocarbon chain)."
• An ester is named the same way as the carboxylic acid it is derived from except that “oic acid” becomes “oate” and the R group of the ester portion is used as prefix.
• An amide is named the same way as the carboxylic acid it is derived from except that “oic acid” becomes “amide” and the R groups of the amide portion are used as prefixes each labeled with N-.
• These structures are examples of what? amides Name them: N-ethyl-N-methylbutanamide  N N-dimethylethanamide   propanamide "
• The order of naming priority for the suffix of organic compounds is: alkane alkyne alkene alcohol ketone aldehyde amide ester anhydride carboxylic acid
• Give the naming prefixes:carboxylic acid:  carboxy-anhydride:  alkanoyloxycarbonyl-ester:   alkoxycarbonyl-amide: amido-aldehyde: oxo-ketone:   keto-alcohol:   hydroxy-alkene:   alkenyl-alkyne:    alkynyl-alkane:   alkyl-
• Give the naming suffixes:carboxylic acid:  -oic acidanhydride:  Anhydrideester:   -oateamide: -amidealdehyde: -alketone:   -onealcohol:   -olalkene:   -enealkyne:    -ynealkane:   -ane
• Some organic naming gotchas to watch for: 1.     For substituents that are alkanes/alkenes/chains longer isn’t higher priority than shorter and fewer isn’t higher priority than more – the priority is determined SOLELY by making the position numbers start with the smallest number possible. 2.     Substituents are ordered ALPHABETICALLY not numerically. With alcohols we want the OH’s numbered as small as possible and it’s still an -ol -diol etc. It only switches to hydroxy if there’s a higher priority substituent (like a ketone or aldehyde).
• Isomers are versions of the same compound that have the same molecular formula but different structures.
• Structural isomers have nothing in common except their molecular formula. They have different chemical and physical properties except for molecular weight.
• Stereoisomers have the same chemical formula and the same atomic connectivity.
• Every isomer must be either a structural isomer or a stereoisomer.
• Stereoisomers are either conformational isomers or configurational isomers.
• Conformational isomers are stereoisomers that differ only in rotation around single (σ) bonds.
• Configurational isomers are stereoisomers that can be interconverted only by breaking bonds.
• This is an example of a Newman projection, in which the molecule (here butane) is visualized along a line extending through a carbon–carbon bond axis. "
• A rotational conformation is called staggered if the side groups in the Newman projection do not overlap and eclipsed if they do overlap.
• The most energetically favored rotational conformation is the anti conformation where the largest groups are 180 degrees apart in the Newman projection. Another rotational conformation having a local energy minimum is the gauche conformation in which the largest groups are 60 degrees apart.
• For compounds larger than butane the name of the conformation is decided by the relative positions of the two largest substituents about a given carbon–carbon bond.
• In this figure, X is an eclipsed conformation, Y is a gauche conformation, and Z is an anti conformation.  "
• The higher the energy of a conformation the less time the molecule will spend in that energetically unfavorable state. However rotational conformational barriers between e.g. anti staggered butane and totally eclipsed butane are small and easily overcome at room temperature.
• The rotational conformation with the highest energy is the totally eclipsed conformation; lowest energy is staggered anti. ""