Abstract: A process for producing a compound of formula (I) is provided. The process comprises reacting a mixture comprising a compound of formula (IIA) and a compound of formula (IIB) with an alkyl alcohol in the presence of a Candida antarctica lipase B enzyme to produce a product comprising the compound of formula (I) and the compound of formula (IIB); wherein R1 is C1 to C6 alkyl; and wherein R2 is II or C1 to C12 alkyl. Also provided are processes for the production of R-lactic acid, oligomeric R-lactic acid, R,R-lactide, poly-R-lactic acid, alkyl S-lactate, S-lactic acid, oligomeric S-lactic acid, S,S-lactide, poly S-lactic acid and stereocomplex polylactic acid.

Abstract: A process for treating a mixture of R,R- and S,S-lactide is provided. The process involves contacting the lactide mixture with an aliphatic alcohol and/or an alkoxide to produce a mixture of R,R- and S,S-aliphatic ester of lactyllactic acid, subsequently contacting the mixture of R,R- and S,S-aliphatic ester of lactyllactic acid with an enzyme to produce a mixture comprising aliphatic ester of lactic acid corresponding to one lactide enantiomer and the aliphatic ester of lactyllactic acid corresponding to the other lactide enantiomer, and recovering the product. Also provided are processes for the production of S-lactic acid, S,S-lactide, poly-S-lactic acid, R-lactic acid, R,R-lactide, poly-R-lactic acid and stereocomplex polylactic acid.

Abstract: A process for treating a mixture of R,R- and S,S-lactide is provided. The process involves contacting the mixture with an aliphatic alcohol and an enzyme in the presence of a ketone solvent to produce a mixture comprising aliphatic ester of lactic acid corresponding to one lactide enantiomer, and the aliphatic ester of lactyllactic acid corresponding to the other lactide enantiomer. Also provided are processes for the production of S-lactic acid, S,S-lactide, poly-S-lactic acid, R-lactic acid, R,R-lactide, poly-R-lactic acid and stereocomplex polylactic acid.

Abstract: A process for treating a mixture of R,R- and S,S-lactide is provided. The process involves contacting the mixture with an aliphatic alcohol and an enzyme to produce a mixture comprising aliphatic ester of lactic acid corresponding to one lactide enantiomer and the aliphatic ester of lactyllactic acid corresponding to the other lactide enantiomer; separating the mixture from the enzyme, and recycling the enzyme to the process; and separating the aliphatic ester of lactic acid from the aliphatic ester of lactyl-lactic acid by fractional distillation. Also provided are processes for the production of S-lactic acid, S,S-lactide, poly-S-lactic acid, R-lactic acid, R,R-lactide, poly-R-lactic acid and stereocomplex polylactic acid.

Abstract: A process for treating a mixture of R,R- and S,S-lactide is provided. The process involves contacting the lactide mixture with an aliphatic alcohol and/or an alkoxide to produce a mixture of R,R- and S,S-aliphatic ester of lactyllactic acid, subsequently contacting the mixture of R,R- and S,S-aliphatic ester of lactyllactic acid with an enzyme to produce a mixture comprising aliphatic ester of lactic acid corresponding to one lactide enantiomer and the aliphatic ester of lactyllactic acid corresponding to the other lactide enantiomer, and recovering the product. Also provided are processes for the production of S-lactic acid, S,S-lactide, poly-S-lactic acid, R-lactic acid, R,R-lactide, poly-R-lactic acid and stereocomplex polylactic acid.

Abstract: A process for treating a mixture of R,R- and S,S-lactide is provided. The process involves contacting the mixture with an aliphatic alcohol and an enzyme to produce a mixture comprising aliphatic ester of lactic acid corresponding to one lactide enantiomer and the aliphatic ester of lactyllactic acid corresponding to the other lactide enantiomer; separating the mixture from the enzyme, and recycling the enzyme to the process; and separating the aliphatic ester of lactic acid from the aliphatic ester of lactyl-lactic acid by fractional distillation. Also provided are processes for the production of S-lactic acid, S,S-lactide, poly-S-lactic acid, R-lactic acid, R,R-lactide, poly-R-lactic acid and stereocomplex polylactic acid.

Abstract: A process for treating a mixture of R,R- and S,S-lactide is provided. The process involves contacting the mixture with an aliphatic alcohol and an enzyme in the presence of a ketone solvent to produce a mixture comprising aliphatic ester of lactic acid corresponding to one lactide enantiomer, and the aliphatic ester of lactyllactic acid corresponding to the other lactide enantiomer. Also provided are processes for the production of S-lactic acid, S,S-lactide, poly-S-lactic acid, R-lactic acid, R,R-lactide, poly-R-lactic acid and stereocomplex polylactic acid.