专业英语教案02烃的命名

第二课烃的命名 一、有关单词 alkanes 链状烷烃 nomenclature 命名法 structural formula 结构式 International Union of Pure and Applied Chemistry (IUPAC) 国际纯粹与应用化学联合会Prefix 词头,前缀 烷烃 饱和开链(非环)烃(CnH2n+2)以-ane作为词尾来命名,前四个烃采用俗名,其余烷烃英文名称的前面部分来自希腊文词头,表示碳原子数目,后接词尾-ane。如果词头中最后一个字母为a,则将a省去。 Si前缀: 0.1 hemi 1 mono 1.5 sesqui 2 di(bis) 3 tri(tris) 4 tetra(tetrakis) 5 penta 6 hexa 7 hepta 8 octa 9 nona 10 deca 11 undeca 12 dodeca 13 trideca 14 tetradeca 15 pentadeca 16 hexadeca 17 heptadeca 18 octadeca 19 nonadeca 20 icosa 21 henicosa 22 docosa 30 triaconta 31hentriaconta 32 dotriaconta 40 tetraconta 41 hentetraconta 42 dotetraconta 50 pentaconta 60 hexaconta 70 heptaconta 80 octaconta 90 nonaconta 100 hectaaconta 110 decahecta 120 icosahecta 130 triacontahecta 132 dotriacontahecta 烷烃命名:见课本 若侧链烷基不只出现一次,用二(di-)、三(tri-)、四(tetra-)等表示。命名时,侧链名称依字母顺序(不包括倍数词头)列出。侧链的名称按全称从第一个字母开始考虑排列顺序。 烷基的命名是把烷烃中的-ane变成-yl 注意词头异(iso-)、新(neo-)、仲(sec-)、叔(tert-)的用法,并注意外文何时使用斜体字。斜体词头不纳入字母顺序排列,因而仲丁基(sec-butyl)列在异丁基(tert-butyl)之前。 如:CH3CH2CH(CH3)2 2-methylbutane CH3CH2CH(CH3)CH2CH3 3-methylpentane CH3CH2CH2CH(CH2CH3)CH2CH2C(CH3)3 5-ethyl-2,2-dimethyloctane CH3CH2CH(CH3)CH2CH2CH(CH2CH3) 3-ethyl-6-methyloctane CH3CH2CH2CH2C(C(CH3)3)2CH2CH(CH3)2 4,4-bis(tert-butyl)-2-methyloctane 亚基的命名:用-ylidene代替-ane。例外:对于甲烷而言,亚甲基methylene而不是methylidene。 Alkanes 烷烃 Ideally, every organic compound should have a name that clearly describes its structure and from which a structural formula can be drawn. 最好每一种有机化合物都有一个能清楚的描述其结构的名字,通过它的名字能画出结构式。For this purpose, chemists throughout the world have accepted a set of rules established by the International Union of Pure and Applied Chemistry (IUPAC). 为此,全世界的化学家们普遍接受一套由国际纯粹与应用化学联合会建立的规则。This system is known as the IUPAC system, or alternatively, the Geneva system because the first meetings of the IUPAC were held in Geneva, Switzerland. 这系统就是IUPAC 系统,因为IUPAC的第一次会议在瑞士的日内瓦举行也叫Geneva系统。The IUPAC name of an alkane with an unbranched chain of carbon atoms consists of two parts: (1) a prefix that indicates the number of carbon atoms in the chain; and (2) the ending -ane, to show that the compound is an alkane. IUPAC 对不带分支的碳原子链的命名分两部分:(1)词头表明链中碳原子的数目;(2)后面的-ane表明化合物是烷烃。Prefixes used to show the presence of from one to 20 carbon atoms are given in Table 1 前缀用来表示1-20之间的碳原子数,如表1所示。 Table 1 prefixes used in the IUPAC system to indicate 1 to 20 carbon atoms in a chain 表1 IUPAC系统中表示链中有1-20个碳原子的前缀 Prefix number of carbon atoms碳原子的前缀 Prefix number of carbon atoms meth 1 undec 11 eth 2 dodec 12 prop 3 tridec 13 but 4 tetradec 14 pent 5 pentadec 15 hex 6 hexadec 16 hept 7 heptadec 17 oct 8 octadec 18 non 9 nonadec 19 dec 10 eicos 20 The IUPAC name of a substituted alkane consists of a parent name, which indicates the longest chain of carbon atoms in the compound, and substituted names, which indicate the groups attached to the parent chain.IUPAC对有取代的烷烃的命名由两部分组成:主链名,表示化合物中最长的碳链的碳原子数目;取代基名,表示连在主链上的取代基。 CH3-CH2-CH2-CH(CH3)-CH2-CH2-CH2-CH2-CH3 A substituent group derived from an alkane is called an alkyl group.由烷烃衍生而来的取代基叫做烷基。The letter R- is commonly used to show the presence of an alkyl group. 通常用字母R-表示烷基的存在。Alkyl groups are named by dropping the -ane from the name of the parent alkane and adding the suffix -yl. 烷基通常是通过去掉母烃的-ane并加上后缀-yl来命名的。For example, the alkyl substituent CH3CH2-is named ethyl.例如,CH3CH2–被命名为乙基。 CH3CH3 CH3CH2- ethane (parent hydrocarbon) ethyl group (an alkyl group) Following are the rules of the IUPAC system for naming alkanes.下面是IUPAC体系命名的 规则: 1. The general name of a saturated hydrocarbon is alkane.饱和的碳氢化合物通常命名为烷烃。 2. For branched-chain hydrocarbon, the hydrocarbon derived from the longest chain of carbon atoms is taken as the parent chain, and the IUPAC name is derived from that of the parent chain.对于支化型碳氢化合物,将含碳原子最多的最长的碳链作为母体,IUPAC的名字就由母链而来。 3. Group attached to the parent chain is called substituents. Each substituent is given a name and a number. The number shows the carbon atom of the parent chain to which the substituent is attached.连在母链上的基团叫做取代基。每个取代基都被赋予一个名字和一个数字。数字表示取代基是连在哪一个母链的碳原子上。 4. If the same substituent occurs more than once, the number of each carbon of the parent chain on which the substituent occurs is given. In addition, the number of times the substituent group occurs is indicated by a prefix di-, tri-, tetra-, penta-, and so on.如果不止一次相同的取代,就要给出母链上每一个碳原子发生该取代的次数。另外,取代基出现的次数的数字用前缀di-.tri-,tetra-,penta-等表示。 5. If there is one substituent, the parent chain is numbered from the end that gives it the lower number. If there are two or more substituents, the parent chain is numbered from the end that gives the lower number to the substituent encountered first.如果只有一次取代,母链从给它最小数字的一端开始标记数字,如果有两种或者更多的取代,母链从给第一个取代基最小数字的一端开始标记。 6. If there are two or more different substituents, they are listed in alphabetical order. When listing substituents, the prefixes iso- and neo- are considered in alphabetizing. The prefixes sec- and tert- are ignored in alphabetizing substituents. Further, the multiplying prefixes di, tri, tetra, and so on are also ignored in alphabetizing substituents.如果有两种或者两种以上不同的取代,取代依照字母的顺序列出。当按字母列出取代时,可以将前缀iso-和neo-考虑进去。前缀sec- 和tert-在按字母顺序表示取代时是不采用的。此外,表示多倍的前缀di, tri, tetra等在这个体系中也不采用。 Alkenes烯烃 Alkanes have a single bond between the carbon atoms. 烷烃碳碳原子间是单键。Alkenes have a double bond (two bonds) between two of the carbon atoms. 烯烃的两个碳原子间是双键。 C=C Consider two carbon atoms connected by a double bond. 考虑到两个碳原子间由一个双键连接。Since this double bond uses four electrons from both carbons, a total of only four hydrogen atoms will satisfy all of the remaining bonds. 因为这种双键要从两个碳原子中占用四个电子,总共只要四个氢原子就能满足所有其它的键。Recall that a single bond represents a pair of shared electrons; a double bond represents two pairs of shared electrons. 回顾一下:单键表示一对共用 的电子;双键表示两对共用的电子。This compound thus becomes CH2=CH2 因此这种化合物为CH2=CH2 And has the molecular formula C2H4. 分子式为C2H4。It is called ethene. 叫做烯烃。 Alkynes炔烃 Consider two carbon atoms connected by a triple bond. 考虑三键连接着的两个碳原子 -C≡C- How many hydrogen atoms must be connected to these two carbon atoms to satisfy all the bond requirements? 这样的两个碳原子必须连接多少氢原子才能满足所有键的要求。The answer is two, so the molecular formula of this compound is C2H2. 答案 八年级地理上册填图题岩土工程勘察试题省略号的作用及举例应急救援安全知识车间5s试题及答案 是两个,因此这种化合物的分子式是C2H2。This compound is called ethyne. 这种化合物称为炔烃。Its structure is 结构是 H-C≡C-H