Geometric isomers are stereoisomers that are distinct and separate because they cannot freely rotate due to a multiple bond or a ring structure. Geometric isomers are generally not optical isomers unless they also happen to have chiral centers. These isomers are superimposable on their mirror images if no chiral centers are present. The isomers are diasteromers according to the definition given here. Show
There are two naming conventions. The older method uses cis- and trans- which works well for the example given above because there are two H atoms and two Cl atoms. But it won’t work well if there were four different atoms involved. The newer method ranks the substituents for each C atom according to the Cahn-Ingold-Prelog sequence rules. (Carey, Organic Chemistry pp. 268-272). If the two with the higher rankings are on the same side of the double bond, that isomer is Z (for the German word zusammen, which means together). The other isomer is E (for entgegen meaning opposite). Briefly, the sequence rules rank the substituents in order of decreasing atomic number and if two or more atoms connected to the C atom are the same the second atom determines the order. Functional Groups Organic chemistry is dominated by the "functional group approach", where organic molecules are deemed to be constructed from:
The functional group approach "works" because the properties and reaction chemistry of a particular functional group (FG) can be remarkably independent of environment. Therefore, it is only necessary to know about the chemistry of a few generic functions in order to predict the chemical behaviour of thousands of real organic chemicals. Organic molecules are also named using the functional group approach:
The rule is that functions assume their distinct identity when separated by –CH2– groups. Thus, the carbonyl, C=O, and hydroxy, OH, of a carboxylic acid, RCOOH, are part of a single function and are NOT "alcohol-plus-ketone": A Couple of Words About The Functional Group Approach The functional group approach is 100% empirical in that it is determined by experiment and experience, and not by theory (unlike VSEPR, for example.) A multifunctional entity like the drug molecule morphine may have several functional groups and chiral centers: Alkane Ethyl: CH3CH2– Propyl: CH3CH2CH2– Isopropyl: (CH3)2CH– Phenyl: C6H5– etc. Alkyl halide Primary alcohol Secondary alcohol Tertiary alcohol Aldehyde Ketone Carboxylic acid Carbonyl function Ester Amide Primary amine Secondary amine Tertiary amine Nitrile Carboxylate ion or salt Amino acid Alkene 1,1-disubstituted: R2C=CH2 1,2-disubstituted: RCH=CHR Alkanes are planar as there is no rotation about the C=C bond. Alkenes are electron rich reactive centres and are susceptible to electrophilic addition. trans-Alkene cis-Alkene Ether From Mark R. Leach 1999-2008 The R represents a carbon based group. More Nomenclature: Alcohols & Ethers: NomenclatureSimple alcohols are named as derivatives of the parent alkane, using the suffix -ol, using the following simple rules:
Aldehydes & Ketones: NomenclatureSimple aldehydes and ketones are named using the standard rules of nomenclature which we have used in the past with the following specific changes:
Nomenclature of Aliphatic AminesSimple amines are named as derivatives of the parent alkane, using the suffix -amine, or by using -amino to name a numbered substituent, using the following rules:
Thus for the following example, you would number from the end closest to the nitrogen, generating the names, 3-methylpentanamine (or 1-amino-3-methylpentane) and 5-methyl-2-hexanamine (or 2-amino-5-methyl-2-hexane), respectively. Which functional groups is characteristic of ketone?ketone, any of a class of organic compounds characterized by the presence of a carbonyl group in which the carbon atom is covalently bonded to an oxygen atom.
What is the functional group for Ketose?A ketose signifies that the sugar contains a ketone functional group.
Which functional group is found in ketones quizlet?The functional group of a ketone is a carbonyl group bonded to two carbon atoms.
Which of these functional groups acts as an acid?The carboxyl group can ionize, which means it can act as an acid and release the hydrogen atom from the hydroxyl group as a free proton (H+).
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