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My teacher said that propan-1-ol can also be named propanol in the latest IUPAC recommendations. I doubt this because Wikipedia only mentions propan-1-ol as the IUPAC name (propanol being relegated to the "other names" section).

im

Is "propanol" an acceptable name?

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The last IUPAC nomenclature recommendations were published in 1993. The current draft documents (release date uncertain) are far more lenient in their acceptance of semi-systematic naming of molecules. Please make sure you understand the differences between the Preferred IUPAC Name (PIN), the retained name, and trivial name.

Propanol is not be the preferred IUPAC name, but significantly, neither is it listed in the tables of Trivial and semisystematic names retained for naming organic compounds. It is, however, a widely accepted name for this chemical, and you are far more likely to encounter propanol in industry than propan-1-ol. Nobody uses propan-1-ol in the real world, even if it is the preferred IUPAC systematic name.

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  • $\begingroup$ If the question in the exam asks: Write the IUPAC name of !im. I answer the question: Propanol, would the answer be technically correct ? $\endgroup$ – user31782 Jul 25 '14 at 4:09
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    $\begingroup$ From IUPAC Nomenclature of Organic Chemistry page : Any name other than a preferred IUPAC name, as long as it is unambiguous and follows the principles of the IUPAC recommendations herein, is acceptable as a ‘general’ IUPAC name, in the context of ‘general’ IUPAC nomenclature. So, perhaps the question is poorly worded, and should read "what is the preferred IUPAC name". $\endgroup$ – long Jul 25 '14 at 4:52
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    $\begingroup$ This is a question that you need to discuss with your teacher. Can it be argued that propanol is unambiguous? Perhaps there is an assumption that substitution is at the one position. If I were marking the exam, and it was testing knowledge of IUPAC nomenclature, I would give you 1 mark for propan-1-ol, and half a mark for answering propanol, n-propanol or propyl alcohol. $\endgroup$ – long Jul 25 '14 at 4:56
  • $\begingroup$ You mean there are two types of IUPAC nomenclature: Gen. IUPAC nom. and Preferred IUPAC num.. I didn't know that. Moreover our book only mentions it as IUPAC nomenclature; no general, no preferred. May be the book isn't perfect. Anyways I got your point. Thank you. $\endgroup$ – user31782 Jul 25 '14 at 10:07
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    $\begingroup$ The last IUPAC nomenclature recommendations were in 2013: dx.doi.org/10.1039/9781849733069-fp001 "Propanol" is still not an acceptable name for propan-1-ol, because there is ambiguity as to whether "propanol" refers to propan-1-ol or propan-2-ol. $\endgroup$ – orthocresol Sep 2 '17 at 13:30
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The most recent IUPAC recommendations for Nomenclature in Organic Chemistry were published in 2013 and supersede the previous 1993 recommendations, which are no longer valid.


Based on the 2013 recommendations, the molecule should be referred to as propan-1-ol as described below:

P-15.1.7.2.1: Alcohols are named by attaching the suffix ‘ol’ to the name of the parent hydride, with elision of the final letter ‘e’ in the parent hydride, if present. When alone in the structure, the characteristic group(s) must receive the lowest locant(s) possible, which is (are) cited immediately in front of the suffix


Propan-1-ol is known as the PIN (preferred IUPAC name), that is the name that you should arrive at through proper application of the recommendations.

IUPAC do allow, however, for 'retained' or 'trivial' names for compounds, so long as their use is unambiguous.

Propanol, on the other hand, is neither a PIN nor a retained name (based on the IUPAC guidelines), as it introduces ambiguity. Are you describing propan-1-ol or propan-2-ol?

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    $\begingroup$ Although I will admit that there is a grain of truth in the other answer’s statement that propan-2-ol is commonly referred to as isopropanol, hence propanol will often be understood (word carefully chosen) as propan-1-ol. $\endgroup$ – Jan Sep 9 '17 at 13:54
  • $\begingroup$ Also according to the obsolete 1993 recommendations, the correct name has already been propan-1-ol. According to the obsolete 1979 recommendations, however, the correct name was 1-propanol. $\endgroup$ – Loong Sep 10 '17 at 11:10
  • $\begingroup$ @Jan However, the name "isopropanol" is incorrect (and also was incorrect according to previous IUPAC recommendations) since there is no hydrocarbon isopropane to which the suffix "-ol"can be added. $\endgroup$ – Loong Sep 10 '17 at 11:13
  • $\begingroup$ @Loong Yes, I never wanted to claim either name be correct. However, isopropanol is widely used both in and outside of laboratories. $\endgroup$ – Jan Sep 10 '17 at 14:54

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