“Pentyl group”的意思、由来-开放百科全书

In organic chemistry, pentyl is a five-carbon alkyl functional group (substituent) with chemical formula -C₅H₁₁. It is the substituent form of the alkane pentane.

In older literature, the common non-systematic name amyl was often used for the pentyl group. Conversely, the name pentyl was used for several five-carbon branched alkyl groups, distinguished by various prefixes.

The name is also used for the pentyl radical, a pentyl group as an isolated molecule. This free radical is only observed in extreme conditions. Its formula is often written "{{chem|C|5|H|11}}•" or "•{{chem|C|5|H|11}}" to indicate that it has one unsatisfied valence bond.

Older "pentyl" groups

Name

Structure

IUPAC status

IUPAC recomm.

Examples

n-pentyl

H|3|C}}−{{chem|({{chem|CH|2}})|4}}−

pentyl

^[2]

tert-pentyl

H|3|C}}−{{chem|CH|2}}−{{chem|({{chem|H|3|C}}-)|2}}-C−

No longer recommended^[1]

2-methylbutan-2-yl (aka (1,1-Dimethylpropyl)^[1]

^[5]

neopentyl

({{chem|H|3|C}}-)|3}}-C−{{chem|CH|2}}−

No longer recommended^[1]

2,2-dimethylpropyl^[1]

^[8]

isopentyl

({{chem|H|3|C}}−)|2}}CH−{{chem|({{chem|CH|2}})|2}}−

No longer recommended^[1]

3-methylbutyl^[1]

^[11]

sec-pentyl

H|3|C}}−{{chem|({{chem|CH|2}})|2}}−({{chem|H|3|C}}−)CH−

pentan-2-yl^[2](or (1-Methylbutyl))

^[13]

3-pentyl

({{chem|H|3|C}}−{{chem|CH|2}}−)|2}}CH−

pentan-3-yl (also known as (1-Ethylpropyl))

^[14]

sec-isopentyl

({{chem|H|3|C}}-)|2}}{{chem|CH}}−{{chem|({{chem|H|3|C}}−)}}CH−

3-methylbutan-2-yl (or (1,2-Dimethylpropyl)

active pentyl

H|3|C}}−{{chem|CH|2}}−({{chem|H|3|C}}−)CH−{{chem|CH|2}}−

2-methylbutyl

Pentyl radical

The free radical pentyl was studied by Pacansky and Gutierrez in 1983. The radical was obtained by exposing bishexanoyl peroxide trapped in frozen argon to ultraviolet light, that caused its decomposition into two carbon dioxide ({{chem|CO|2}}) molecules and two pentyl radicals.

Examples

References

1. ^¹²³⁴⁵{{cite book | title = Nomenclature of Organic Chemistry : IUPAC Recommendations and Preferred Names 2013 (Blue Book) | publisher = The Royal Society of Chemistry | date = 2014 | location = Cambridge | page = 607 | doi = 10.1039/9781849733069-FP001 | isbn = 978-0-85404-182-4}}
2. ^{{cite book | title = Nomenclature of Organic Chemistry : IUPAC Recommendations and Preferred Names 2013 (Blue Book) | publisher = The Royal Society of Chemistry | date = 2014 | location = Cambridge | page = 362 | doi = 10.1039/9781849733069-FP001 | isbn = 978-0-85404-182-4}}
3. ^¹isopentyl group at CHEBI. Accessed on 2013-02-21.
4. ^¹Pentan-3-yl group at CHEBI. Accessed on 2013-02-21.
5. ^¹n-pentyl nitrite, described as "a nitrite ester having n-pentyl as the alkyl group." Accessed on 2013-02-21.
6. ^¹Pentobarbital at CHEBI, described as "Barbituric acid substituted at C-5 by ethyl and sec-pentyl groups". Accessed on 2013-02-21.
7. ^¹neopentyl at CHEBI. Accessed on 2013-02-21.
8. ^¹NCBI, [https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=6405 tert-pentyl alcohol] in PubChem. Accessed on 2013-02-21.