2.9 Applying the IUPAC Rules: The Names of the CaHi isomers A BRIEF HISTORY OF SYSTEMATIC ORGANIC NOMENCLATURE he first successful formal system of chemical pounds can have the same name, it is incorrect to be- nomenclature was advanced in France in 1787 lieve that there is only a single IUPAC name for a par to replace the babel of common names which ticular compound. then plagued the science. Hydrogen (instead of"in- The 1993 IUpac recommendations and theil flammable air" )and oxygen (instead of"vital air") more widely used 1979 predecessors may both be are just two of the substances that owe their modern accessed at the same web site names to the proposals described in the Methode de nomenclature chimique. It was then that important www.acdlabs.com/iupadnomenclature compounds such as sulfuric, phosphoric, and carbonic acid and their salts were named the guidelines were The IUPAC rules are not the only nomenclature more appropriate to inorganic compounds; it was not stem in use today. Chemical Abstracts Service sur- until the 1830s that names reflecting chemical com- veys all the worlds leading scientific journals that position began to appear in organic chemistry ublish papers relating to chemistry and publishes In 1889, a group with the imposing title of the brief abstracts of those papers. The publication International Commission for the Reform of Chemical Chemical Abstracts and its indexes are absolutely es- try. For Nomenclature was organized, and this group in turn, Chemical Abstracts nomenclature was very similar to ponsored a meeting of 34 prominent European IUPAC nomenclature but the tremendous explosion hemists in Switzerland in 1892. Out of this meeting arose a system of organic nomenclature known as the Chemical Abstracts to modify its nomenclature so Geneva rules. The principles on which the Geneva that its indexes are better adapted to computerized rules were based are the forerunners of our present searching This means that whenever feasible, a com- ystem 1911, but the intrusion of World War I prevented any ent from any of the several IUPAC names. In general national Union of Chemistry was established in 1930 and undertook the necessary revision leading to pub. chemical structure and its IUPAC name than its Chem- lication in 1930 of what came to be known as the ical Abstracts name. Liege rules It is worth noting that the generic name of a After World War I, the International Union of drug is not directly derived from systematic nomen- Chemistry became the International Union of Pure clature. Furthermore, different pharmaceutical com- and Applied Chemistry(known in the chemical com- panies will call the same drug by their own trade munity as the /UPAO). Since 1949, the IUPAC has is ame, which is different from its generic name. Generic names are invented on request (for a fee)by sued reports on chemical nomenclature on a regular the U.S. Adopted Names Council, a private organiza- basis. The most recent IUPAC rules for organic chem istry were published in 1993. The IUPAC rules often the american pharmaceutical association. and the pound. Thus although it is true that no two com- I.S. Pharmacopeial Convention In this case, the longest continuous chain has five carbon atoms; the compound is named as a derivative of pentane. The key word here is continuous. It does not matter whether the carbon skeleton is drawn in an extended straight-chain form or in one with many bends and turns. All that matters is the number of carbons linked together in an Step 2 Identify the substituent groups attached to the parent chain. The parent pentane chain bears a methyl( CH3) group as a substituent. Back Forward Main MenuToc Study Guide ToC Student o MHHE WebsiteIn this case, the longest continuous chain has five carbon atoms; the compound is named as a derivative of pentane. The key word here is continuous. It does not matter whether the carbon skeleton is drawn in an extended straight-chain form or in one with many bends and turns. All that matters is the number of carbons linked together in an uninterrupted sequence. Step 2 Identify the substituent groups attached to the parent chain. The parent pentane chain bears a methyl (CH3) group as a substituent. 2.9 Applying the IUPAC Rules: The Names of the C6H14 Isomers 63 A BRIEF HISTORY OF SYSTEMATIC ORGANIC NOMENCLATURE The first successful formal system of chemical nomenclature was advanced in France in 1787 to replace the babel of common names which then plagued the science. Hydrogen (instead of “in- flammable air”) and oxygen (instead of “vital air”) are just two of the substances that owe their modern names to the proposals described in the Méthode de nomenclature chimique. It was then that important compounds such as sulfuric, phosphoric, and carbonic acid and their salts were named. The guidelines were more appropriate to inorganic compounds; it was not until the 1830s that names reflecting chemical com￾position began to appear in organic chemistry. In 1889, a group with the imposing title of the International Commission for the Reform of Chemical Nomenclature was organized, and this group, in turn, sponsored a meeting of 34 prominent European chemists in Switzerland in 1892. Out of this meeting arose a system of organic nomenclature known as the Geneva rules. The principles on which the Geneva rules were based are the forerunners of our present system. A second international conference was held in 1911, but the intrusion of World War I prevented any substantive revisions of the Geneva rules. The Inter￾national Union of Chemistry was established in 1930 and undertook the necessary revision leading to pub￾lication in 1930 of what came to be known as the Liège rules. After World War II, the International Union of Chemistry became the International Union of Pure and Applied Chemistry (known in the chemical com￾munity as the IUPAC). Since 1949, the IUPAC has is￾sued reports on chemical nomenclature on a regular basis. The most recent IUPAC rules for organic chem￾istry were published in 1993. The IUPAC rules often offer several different ways to name a single com￾pound. Thus although it is true that no two com￾pounds can have the same name, it is incorrect to be￾lieve that there is only a single IUPAC name for a par￾ticular compound. The 1993 IUPAC recommendations and their more widely used 1979 predecessors may both be accessed at the same web site: www.acdlabs.com/iupac/nomenclature The IUPAC rules are not the only nomenclature system in use today. Chemical Abstracts Service sur￾veys all the world’s leading scientific journals that publish papers relating to chemistry and publishes brief abstracts of those papers. The publication Chemical Abstracts and its indexes are absolutely es￾sential to the practice of chemistry. For many years Chemical Abstracts nomenclature was very similar to IUPAC nomenclature, but the tremendous explosion of chemical knowledge in recent years has required Chemical Abstracts to modify its nomenclature so that its indexes are better adapted to computerized searching. This means that whenever feasible, a com￾pound has a single Chemical Abstracts name. Unfor￾tunately, this Chemical Abstracts name may be differ￾ent from any of the several IUPAC names. In general, it is easier to make the mental connection between a chemical structure and its IUPAC name than its Chem￾ical Abstracts name. It is worth noting that the generic name of a drug is not directly derived from systematic nomen￾clature. Furthermore, different pharmaceutical com￾panies will call the same drug by their own trade name, which is different from its generic name. Generic names are invented on request (for a fee) by the U.S. Adopted Names Council, a private organiza￾tion founded by the American Medical Association, the American Pharmaceutical Association, and the U.S. Pharmacopeial Convention. Back Forward Main Menu TOC Study Guide TOC Student OLC MHHE Website