Table 4.

Examples of using the click chemistry reaction to obtain new alginate derivatives.

Click Reaction	Functional Groups Involved in Reaction	Characteristic
Copper-(I)-Catalyzed Azide-Alkyne Cycloaddition (CuAAC)	Azide–Alkyne	Cu-catalyzed (cytotoxic and difficult to remove from product) Reversible Bioorthogonal No side product
Strain-Promoted Alkyne-Azide Cycloaddition (SPAAC)	Azide–cyclic Alkyne	No catalyst needed Hydrophobicity of alkyne ring hindering the reaction
Inverse Electron Demand Diels–Alder Cycloaddition (IEDDA)	Dienophile–Diene	No catalyst needed
Diels–Alder Reaction	Diene–Alkene	No catalyst needed Thermally reversible
Thiol-Ene Addition	Alkene–Thiol	Photoinitiator needed Spatial and temporal control
Thiol-Michael Addition Click Reactions	Thiol–α,β-Unsaturated carbonyl compound	No catalyst needed Mild conditions
Thiol-Yne Addition	Alkyne–Thiol	Initiator needed
Oxime Coupling	Aminooxy compound–Aldehyde/Ketone	No catalyst needed Fast reaction under mild conditions