Prefix Number of C ons meth... 1 eth... 乙 prop.… 23 but.… 丙丁 pent... hex.… 6 hept.… 7 oct... 戊己庚辛壬 non... 9 dec.… 10 癸 n。normal R…generic group (rest of the molecule)
甲 乙 丙 丁 戊 己 庚 辛 壬 癸 n… normal R…generic group (rest of the molecule)
(Be able to recognize these common fragments.) Some alkyl groups have nonsystematic,common names methyl- ethyl- n-propyl- ；-Me ；-CH Et CHs nPr CH3 甲基 乙基 丙基 iso-propyl- iso-butyl- (i-methylethyl--)） 异丙基 CH3 丁基 n-butyl- (2-methylpropyl-) 异丁基 Pr ；-Bu CH3 ；Bu CH3 2 3 CH3 仲丁基 叔丁基 新戊基 sec-butyl- tert-butyl- neopentyl- (1-methylpropyl-） (1,1-dimethylethyl-) (2,2-dimethylpropyl) CH3 2CH3 HaC CH3 3 -Bu ；-Bu3个CH 2 CH3 2 H
甲基 乙基 丙基 异丙基 丁基 异丁基 仲丁基 叔丁基 新戊基 Some alkyl groups have nonsystematic, common names
Naming Alkanes Four steps 1.Find the parent hydrocarbon the longest continuing chain of carbon with the larger number of branch points 2.Number the atoms in the parent chain-- beginning the nearer 3.Identify and number the substituents 4.Write the name as a single word write substituents in alphabetical order the multiplier prefixes di,tri,tetra-,and so forth.Do not use these prefixes when alphabetizing
Naming Alkanes Four steps 1. Find the parent hydrocarbon the longest continuing chain of carbon with the larger number of branch points 2. Number the atoms in the parent chain-- beginning the nearer 3. Identify and number the substituents 4. Write the name as a single word write substituents in alphabetical order the multiplier prefixes di-, tri-, tetra-, and so forth. Do not use these prefixes when alphabetizing 位次
Naming Alkanes Four steps 1.Find the parent hydrocarbon a)Find the longest continuing chain of carbon atoms in the molecule b)If two different chains of equal length are present, choose the one with the larger number of branch points as the parent CH3 CH3 CH3CHCHCH2CH2CH3 CH3CH-CHCH2CH2CH3 CH2CH3 CH2CH3 Named as a hexane with NOT as a hexane with two substituents one substituent
Naming Alkanes Four steps 1. Find the parent hydrocarbon a) Find the longest continuing chain of carbon atoms in the molecule b) If two different chains of equal length are present, choose the one with the larger number of branch points as the parent
Naming Alkanes 2.Number the atoms in the parent chain aNumber each carbon atom in the parent chain beginning at end nearer the first branch point 2 67 CH2CH3 CH2CH3 CH3-CHCH-CH2CH3 NOT CH3-CHCH-CH2CH3 314 54 CH2CH2CH3 CH2CH2CH3 567 321 b)If there is a branching point at an equal distance from both ends of the parent chain,begin numbering at the end nearer the second branch point 89 21 CH2CH3 CH3 CH2CH3 CH2CH3 CH3 CH2CH3 CH3-CHCH2CH2CH-CHCH2CH3 NOT CH3-CHCH2CH2CH-CHCH2CH3 7654321 3456789
Naming Alkanes 2.Number the atoms in the parent chain a)Number each carbon atom in the parent chain beginning at end nearer the first branch point b)If there is a branching point at an equal distance from both ends of the parent chain, begin numbering at the end nearer the second branch point