ORG CHEM | Functional Groups

Functional Groups

specific groups of atoms within molecules that determine the characteristic chemical reactions of those molecules

Alkenes | Definition

has at least one carbon-carbon double bond

Alkenes | Bonding

C=C

Alkenes | Polarity

nonpolar because it is mainly composed of carbon and hydrogen, which have a low electronegativity difference, and the carbon-carbon double bond (C=C) doesn't create a significant difference in electronegativity between the carbon atoms

Alkenes | Solubility

generally insoluble in water due to their nonpolar nature but soluble in organic solvents such as hexane or toluene

Alkenes | Importance

used extensively in the chemical industry for polymer production; building blocks in synthesis, reactive in addition reactions due to double bond

Alkenes | Biological Function

key intermediates in biosynthesis pathways, such as the formation of essential fatty acids in biological membranes in natural product in plant defense like (terpenes)

Alkynes | Definition

has at least one carbon-carbon triple bond

Alkynes | Bonding

C≡C

Alkynes | Polarity

nonpolar due to the triple bond between two carbon atoms (C≡C), with a minimal electromagnetivity difference

Alkynes | Solubility

insoluble in water but soluble in organic solvents, similar to alkenes.

Alkynes | Importance

used to create a variety of complex organic molecules, such as acetylene being used in welding torches due to its high-energy bonds; used in chemical synthesis and highly reactive

Alkynes | Biological Functions

less common in biological systems but can be found in some natural products and antibiotics; intermediates in biosynthetic pathways

Alcohols | Definition

has one or more hydroxyl groups (-OH)

Alcohols | Bonding

R-OH

Alcohols | Polarity

polar because of the hydroxyl group (-OH), where oxygen is more electronegative than hydrogen, leading to a significant dipole

Alcohols | Solubility

highly soluble in water due to their ability to form hydrogen bonds. As the hydrocarbon chain length increases, solubility decreases.

Alcohols | Importance

used as solvents, fuels, disinfectants, and intermediates in the production of many chemicals, such as how ethanol is used in alcoholic beverages and as a biofuel; engage in hydrogen bonding

Alcohols | Biological Function

are important in metabolism, e.g. glucose is metabolized into alcohol in the fermentation process; are also present in fats and lipids as glycerol; important in synthesis of lipids and carbohydrates

Thiols | Definition

has a sulfhydryl group (-SH)

Thiols | Bonding

R-SH

Thiols | Polarity

slightly polar due to the sulfur-hydrogen bond, but sulfur is less electronegative than oxygen, so these are less polar than alcohols

Thiols | Solubility

less soluble in water compared to alcohols but can still dissolve due to the sulfur's ability to form weak hydrogen bonds

Thiols | Importance

used in the chemical industry for creating rubber and plastics and in the pharmaceutical industry for synthesizing drugs; reducing agents

Thiols | Biological Function

has a crucial role in proteins, like in the amino acid cysteine. This group helps form disulfide bridges that stabilize protein structure; used in antioxidant activity in metabolic pathways

Arenes | Definition

has a benzene ring

Arenes | Bonding

there is a ring with alternating single and double bonds

Arenes | Polarity

generally nonpolar because of the symmetrical distribution of electrons in the benzene ring an the delocalization of electrons in aromatic ring

Arenes | Solubility

insoluble in water but dissolve well in nonpolar solvents like benzene and toluene

Arene | Importance

fundamental in the synthesis of dyes, fragrances, plastics, and pharmaceuticals; Benzene, toluene, and xylene (BTX) are major petrochemical products; are generally stable

Arene | Biological Function

present in many biologically important molecules, such as hormones, vitamins, amino acids (tyrosine and phenylalanine) and neurotransmitters like dopamine; critical for biological processes

Alkyl Group

an alkane missing one hydrogen atom

Aryl Group

a functional group or substituent from an aromatic ring

Ethers | Definition

has an oxygen atom bonded to two alkyl or aryl groups

Ethers | Bonding

R-O-R, such that R is either an akyl/aryl group

Ethers | Polarity

moderate polarity due to the more electronegative oxygen atom, which has lone pairs and creates a dipole moment. However, the lack of hydrogen bonding makes them less polar than alcohols, as it is bonded to two alkyl/aryl groups

Ethers | Solubility

less soluble in water than alcohols but more soluble than alkanes; are good solvents for nonpolar and moderately polar compounds

Ethers | Importance

are used as solvents in laboratories and industries as they are not reactive and can dissolve many compounds; diethyl ether was once widely used as an anesthetic

Ethers | Biological Function

are notably present in lipids, where they contribute to the structure and function of cell membranes; important in biological signalling (e.g. in lipids); are anesthetics

Alkyl Halides | Definition

a halogen bonded to an alkyl group

Alkyl Halides | Bonding

R-x such that x is F, Cl, Br, or I

Alkyl Halides | Polarity

polar due to the bond between the carbon and the highly electronegative halogen atom, creating a dipole moment.

Alkyl Halides | Solubility

Dependent on size, as smaller kinds of these group are slightly soluble while larger ones are insoluble; they are soluble in organic solvents

Alkyl Halides | Importance

used in the production of refrigerants, solvents, agrochemicals and in pharmaceuticals (e.g. halothane as an anesthetic); undergo nucleophilic substitution and elimination reactions as valuable intermediates

Alkyl Halides | Biological Function

they are not common in biological systems but can be toxic; they are intermediates in organic reactions such as substitutions and eliminations, making them bioactive and common in biochemical pathway