ChEBI: Glycine betaine hydrate is a hydrate that is the monohydrate form of glycine betaine. It has a role as a fundamental metabolite. It contains a N,N,N-trimethylglycinium.
Crystallise betaine from aqueous EtOH or EtOH/Et2O. The monohydrate loses H2O above 100o. Betaine undergoes internal alkylation to methyl dimethylaminoacetate Purification of Biochemicals — Amino Acids and Peptides above its melting point. It is also prepared by treating the hydrochloride (below) with silver oxide and recrystallising from EtOH/Et2O. [Edsall J Am Chem Soc 66 1767 1943, Leifer & Lippincott J Am Chem Soc 79 5098 1957, for pK see Grob et al. Chem and Ind (London) 1222 1955, Beilstein 4 III 1127, 4 IV 2369.]