11/2/2009 Overview Survey of Key Functional Groups Ch 8.1 Chem 201 – Functional Group Survey 11/2/2009 Overview Overview Chem 201 – Functional Group Survey 11/2/2009 Chem 201 – Functional Group Survey 11/2/2009 1 11/2/2009 Concerns Functional Group Names Getting overwhelmed Alcohol Strange new formulas Strange new names Strange new reagents Alkyl halide, Haloalkane Many new relationships leads to brain meltdown !!! Info builds ONE step at a Thiol time Ch 8 surveys FG Names, drawings, properties No new reactions (almost) Ether Sulfide Chem 201 – Functional Group Survey 11/2/2009 Chem 201 – Functional Group Survey 11/2/2009 RX Names Common or Substitutive (IUPAC)? Special Compounds Use Common Names Alkyl halide Haloalkane Haloforms Alkyl group attached Halogen substitutent methylene chloride to Halogen attached to Alkane chloroform ()(dichloromethane) bromoform Methyl chloride Chloromethane iodoform Ethyl bromide Bromoethane Useful solvents Special compounds carbon tetrachloride - hydrophobic Special groups - moderately polar carbon tetrabromide - volatile methylene, allyl, vinyl, benzyl but all linked to health problems Special history allyl bromide these slides will be posted Chem 201 – Functional Group Survey 11/2/2009 Chem 201 – Functional Group Survey 11/2/2009 2 11/2/2009 Give “haloalkane” (IUPAC) names Give “haloalkane” (IUPAC) names 2- fluoropropane cis-121,2-dibromocyc lo hexane Chem 201 – Functional Group Survey 11/2/2009 Chem 201 – Functional Group Survey 11/2/2009 ROR’ Names ROR’ Names Common & Substitutive Additional considerations Dialkyl ether Alkoxyalkane 1,2-dimethoxyethane 2 Alkyl groups attached Alkoxy (RO) substitutent to oxygen make Ether attached to Alkane (R’) Tetrahydrofuran Many special rings (THF) furan Diethyl ether (“ether”) Alkoxy = alkyl (R) + oxy Methyl tert-butyl ether Alkane = alkyl (R’) + ane (MTBE) oxirane EhEthoxyet hane epoxide “alkene” oxide 2-Methoxy-2-methylpropane 1,4-dioxane anisole Chem 201 – Functional Group Survey 11/2/2009 Chem 201 – Functional Group Survey 11/2/2009 3 11/2/2009 RSR’ Names Common & Substitutive RX, ROR’, RSR’ name similarities Dialkyl sulfide (Alkylthio)alkane Common names used widely 2 Alkyl groups attached Alkylthio (RS) substitutent Special compounds (names often break “common” rules) to slfrsulfur make Sulfide attached to Alkane (R’) Ring s (ROR, RSR only) Alkylthio = alkyl (R) + thio IUPAC Alkane = alkyl (R’) + ane Substituted alkane Haloalkane Alkoxyalkane ethyl methyl sulfide (Alkylthio)alkane (methylthio)ethane Chem 201 – Functional Group Survey 11/2/2009 Chem 201 – Functional Group Survey 11/2/2009 ROH, RSH name similarities Alcohol names - common or IUPAC? Common names used Common names are fading out Special compounds Special groups IUPAC New suffix replaces “alkane” allyl alcohol benzyl alcohol ROH, alkanol RSH, alkanethiol Special compounds ethylene glycol glycerol Chem 201 – Functional Group Survey 11/2/2009 Chem 201 – Functional Group Survey 11/2/2009 4 11/2/2009 IUPAC - Alkanol IUPAC - Alkanethiol Parent chain = longest chain bearing OH Parent chain = longest chain bearing SH Alkanol = alkane + ol Keep ‘e’ from alkane Parent = alkanol Parent = alkanethiol # = posit ion of OH Add ‘thio l’ (o ne word) give smallest # possible 2-chlorocyclopentanol # = position of SH always #1 in ring cis-2-chlorocyclopentanol give smallest # possible (1R,2S)-2-chlorocyclopentanol Common always #1 in ring 4-methyl-3-penten-1-ol tert-butyl mercaptan 2-pentanol 1,2-ethanediol 2-pentanethiol pentan-2-ol ethane-I, 2-diol pentane-2-thiol Chem 201 – Functional Group Survey 11/2/2009 Chem 201 – Functional Group Survey 11/2/2009 When groups compete: alcohol vs. thiol IUPAC Rules (p. 327) 1. Identify the principal group How would you name this? a. Rank candidates (OH beats SH) 2. Identif y the priilincipal chihain 5 C chain. Could be… a. Chain contains principal group(s) some kind of I-pentanol b. Chain contains max. number double & triple bonds, etc. some kind of 2-pentanethiol 3. Number the principal chain Who wins? OH or SH? a. Lowest # for C bearing principal group And how do yygpou name other group as substituent? b. Lowest # for multiple bonds, etc. 4. Construct name IUPAC Rules !!! a. Name principal chain, group, and # b. Name substituents and #’s Chem 201 – Functional Group Survey 11/2/2009 Chem 201 – Functional Group Survey 11/2/2009 5 11/2/2009 But IUPAC rules are problematic Chem 201 simplification Complicated I will only give you naming problems for compounds Must fill in etc. (several rules) that contain ONE principal group MstMust know princirincialpal group rankings YoYou u dond o n ’t need to learn principal group rankings Must know substituent names You don’t need to learn substituent names OH O SH 6-hydroxy-7-mercaptooctan-4-one And IUPAC names are not even universally accepted But … I will expect you to be able to work with more complicated names when I provide them Chem 201 – Functional Group Survey 11/2/2009 Chem 201 – Functional Group Survey 11/2/2009 Typical naming problems Typical naming problems Draw 5-(ethylthio)-2-methylheptane Draw 5-(ethylthio)-2-methylheptane Draw an oxirane Draw an oxirane Chem 201 – Functional Group Survey 11/2/2009 Chem 201 – Functional Group Survey 11/2/2009 6.