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8

Apart from the numbering system help distinguish between various isomers (see @DrMoishePippik's answer), it also helps grouping compounds into various series: 000 series: methane-based compounds 100 series: ethane-based compounds 200 series: propane-based compounds 300 series: cyclic organic compounds 400 series: zeotropes 500 series: azeotropes 600 ...


6

Some "hydrofluorocarbons" used in refrigeration and other applications actually are fluorocarbons, sans hydrogen. To make numbering unambiguous, even tetrafluoromethane, $\ce{CF4}$, which is "R-14" in ASHRAE parlance, would be 114 in that HFC nomenclature. Manufacturers use proprietary and somewhat arbitrary nomenclature. For example, ...


18

Does folic acid contain a benzyl or a phenyl group? This is the question asked in the title. At the first glance to the structure, one would say folic acid consists of phenyl function but not benzyl function because the question did not define what is the phenyl group. In reality, phenyl group $(\ce{Ph})$ is $\ce{C6H5}$. As Poutnik pointed out in the ...


2

Taken from the answer to In Parent chain choosing should one consider longest chain or chain with more substituents? by Loong. From the Nomenclature of Organic Chemistry – IUPAC Recommendations and Preferred Names 2013 (Blue Book) P-45.2.1 The preferred IUPAC name is based on the senior parent structure that has the maximum number of substituents cited as ...


2

Many years ago ago I dealt with [PMo$_{12}$O$_{40}$(VO)$_2$]$^{q−}$, which is basically a Keggin polyoxomolybdate (-3) capped with two vanadyl groups (2*(+2)). It was in a highly reduced form, but depending on how many blue electrons were residing in the Keggin cage, it might conceivably present neutral or positive charge. My work was theoretical and ...


6

According to Chemdraw JS' Structure to Name feature which generally gives the PIN of the molecule, the PIN for $\ce{(CCl3)3CCl}$ is 1,1,1,2,3,3,3-heptachloro-2-(trichloromethyl)propane From Nomenclature of Organic Chemistry – IUPAC Recommendations and Preferred Names 2013 (Blue Book), P-14.5 ALPHANUMERICAL ORDER Alphanumerical order has been commonly ...


1

As I mentioned in the comments, the carbocations are named in the same vein as the alkyl functional group/side chains are named. To some extent, you have to learn which structure the names correspond to. Look at Alkyl at wikipedia for the names of some alkyl groups. For example: This is the isopropyl group. When drawing the isopropyl cation, you will draw ...


7

In this case, there are 3 stereogenic centers, they are $\ce{C-3}$, $\ce{C-4}$, $\ce{C-5}$ $\ce{C-3}$,$\ce{C-5}$ are straightforward. Using the main CIP rules (1-3), we get $\ce{C-3}$ to be $R$ and $\ce{C-5}$ to be $S$ The term 'pseudoasymmetric' is defined in Subsection P-92.1.1 (d) of the IUPAC Blue Book as follows. Stereogenic units are called ...


6

As noted by Safdar, the two chiral compounds are meso-compunds. Like for meso-tartaric acid, there a is a mirror plane in the molecule. It is possible to name them unambiguously, too. You may use a page like the one about e.g., ChemDraw to train yourself in this part of chemical nomenclature: While the compound is chiral, it is better to speak about the ...


4

The central $\ce{C}$ is said to be pseudochiral. This means that its chirality will depend upon the configuration of the branches attached to it. For example, in the compounds you've drawn, the central $\ce{C}$ indeed is, in fact, achiral. They are diastereomers and not enantiomers, and both are meso compounds, hence optically inactive. However, if you had ...


5

This answer is similar to this answer on $\ce{[Co(NH3)5(H2O)]Cl3}$, Thanks to Loong (Faded Giant) for the references. According to the current version of Nomenclature of Inorganic Chemistry – IUPAC Recommendations 2005 (Red Book), the systematic names of coordination entities are generated by using the following principles: IR-9.2.2.1 Sequences of ligands ...


2

Professor Jonathan M Goodman gave an explanation on the InChi mailing list: https://sourceforge.net/p/inchi/mailman/inchi-discuss/thread/B7D99356-8B55-43BE-8C2A-B8CC3EB37799%40cam.ac.uk/#msg37289766 In summary, the given class of molecules represents a special case where the current InChi algorithm (1.06) produces less than useful results in order to being ...


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