In organic chemistry, a thiol θaɪɒl; from Ancient Greek θεῖον (theion) ‘sulfur’, or thiol derivative, is any organosulfur compound of the form R−SH, where R represents an alkyl or other organic substituent. The −SH functional group itself is referred to as either a thiol group or a sulfhydryl group, or a sulfanyl group. Thiols are the sulfur analogue of alcohols (that is, sulfur takes the place of oxygen in the hydroxyl (−OH) group of an alcohol), and the word is a blend of “thio-” with “alcohol”.
Many thiols have strong odors resembling that of garlic or rotten eggs. Thiols are used as odorants to assist in the detection of natural gas (which in pure form is odorless), and the “smell of natural gas” is due to the smell of the thiol used as the odorant. Thiols are sometimes referred to as mercaptans (/mərˈkæptæn/) or mercapto compounds, a term introduced in 1832 by William Christopher Zeise and is derived from the Latin mercurio captāns (‘capturing mercury’) because the thiolate group (RS−) bonds very strongly with mercury compounds.[8]
Structure and bonding
Thiols having the structure R−SH, in which an alkyl group (R) is attached to a sulfhydryl group (SH), are referred to as alkanethiols or alkyl thiols. Thiols and alcohols have similar connectivity. Because sulfur atoms are larger than oxygen atoms, C−S bond lengths – typically around 180 picometres – are about 40 picometers longer than typical C−O bonds. The C−S−H angles approach 90° whereas the angle for the C−O−H group is more obtuse. In solids and liquids, the hydrogen-bonding between individual thiol groups is weak, the main cohesive force being Van der Waals interactions between the highly polarizable divalent sulfur centers.
The S−H bond is much weaker than the O−H bond as reflected in their respective bond dissociation energies (BDE).
An S−H bond is moderately polar because of the small difference in the electronegativity of sulfur and hydrogen. In contrast, O−H bonds in hydroxyl groups are more polar. Thiols have a lower dipole moment relative to their corresponding alcohols.
Nomenclature
There are several ways to name the alkylthiols:
The suffix -thiol is added to the name of the alkane. This method is nearly identical to naming an alcohol and is used by the IUPAC, e.g. CH3SH would be methanethiol.
The word mercaptan replaces alcohol in the name of the equivalent alcohol compound. Example: CH3SH would be methyl mercaptan, just as CH3OH is called methyl alcohol.
The term sulfhydryl- or mercapto- is used as a prefix, e.g. mercaptopurine.
As Thoils are part of the greening process of grapes and other plants and Thoils are part of the alcohol content of plants is it likely that to create a fire the laser would be set at frequencies to set the vegetation alight as Trumpet Number One indicates?
Disasters are detailed in the Bible. These manmade disasters described by Angels sounding God's warnings in the form of a war time instrument called a Trumpet
