IUPAC&Nomenclature&Rul es:&N a ming&Alkanes&&1. There&are&2&parts&to&every&alkane&name:&&&&2. Find&the&longest(carbon(chain.&If&there&are&2&or&more&chains&of&equal&length,&then&maximize&the&quantity&of&substituents.&&&&For&example:&&&Choose&the&set&of&highlighted&carbon&atoms&on&the&left&as&the&parent(carbon(chain,¬&the&set&on&the&right,&because&the&one&on&the&left&has&2&substituents&and&the&one&on&the&right&only&has&one.&&Note,&it&may&be&necessary&to&‘turn&corners’&to&identify&the&longest&carbon&chain&(the&parent).&&Parent&alkane&names&are&on&pg&47,&Table&2.2.&&3. Identify(the(substituents(on(the(parent(carbon(chain.&&You’ll&find&a&substituent,&whenever&you&come&to&a&branch&point&along&the&parent&chain.&You(can(find(the(names(of(common(substituents(in(Table(293,(pg(48(and(on(pg(51.&&They&have&names&like&methyl,ðyl,&propyl,&isopropyl,&and&tertQbutyl&depending&on&the&number&of&carbons&in&the&substituent&and&which&carbon&atom&of&the&substituent&is&bonded&to&the&parent.&&In&the&example&above&on&the&left,&there&is&one&methyl&substituent&and&oneðyl&substituent.&&In&the&examples&below,&the&left&molecule&has&a&propyl&substituent,&the&one&on&the&right&has&an&isopropyl&substituent.&&&&4. Number(the(carbon(atoms(of(the(parent(chain.&&In&order&to&describe&the&location&of&the&substituents&on&the&parent&chain,&number&each&carbon&atom&of&the&parent&carbon&chain.&&There&will&always&be&2&possible&ways&to&number&the&Pre-fixParentLongest Carbon ChainLocation and identity of every substituent on the parentSubstituents are atoms or groups of atoms (other than H)that are bonded to the parent.H3C CHHCCH2CH3CH3CH2CH2H3C CHHCCH2CH3CH3CH2CH2CH3CH3H3C CH2CH2CH2CHCH2CH2CH2HCH3C CH3CH3H3C CH2CH2CH2CHCH2CH2CH2H2CCH2CH3CH3chain,&because&there&are&2&ends&to&a&chain.&&&Always&start&at&the&end&closest&to&the&first&branch&point.&&If&the&first&branch&points&are&the&same&distance&from&each&end,&continue&on&and&use&the&second&branch&point&as&the&tie&breaker.&&Below,&the&one&on&the&left&is&numbered&correctly:&&&5. Use(the(carbon(numbers(to(describe(the(location(of(the(substituents.&&If&more&than&one&of&the&same&kind&of&substituent&is&present,&use&the&descriptors&di,&tri,&tetra,&penta,&etc.&&In&the&example&above,&the&correct&name&is:&2,3,5Qtrimethylhexane.&&&&6. Put(the(name(together.&&Now&that&all&of&the&pieces&of&the&name&are&determined;&the&parent&chain,&the&substituents,&the&numbering,&it’s&important&to&assemble&the&pieces&correctly.&&a. Alphabetize&substituents&by&substituent&name,&soðyl&comes&before&dimethyl.&&&b. Punctuation&counts.&&Dashes&separate&numbers&from&letters&and&commas&separate&numbers&from&numbers.&No&spaces.&&c. Make&sure&every&substituent&has&a&number,&even&if&the&substituents&are&on&the&same&carbon&atom:&&&2,2Qdimethylpropane¬&2Qdimethylpropane&&&&&&&H3C CH CH CH2CH CH3CH3CH3CH3H3C CH CH CH2CH CH3CH3CH3CH31 2 3456612345H3C C
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