Amphoteric ester sulfonates

A mixture comprising at least two compounds having the formula 1:

• wherein
• R is C3-C23 hydrocarbyl;
• R1 is C1-C8 hydrocarbyl;
• R2 and R3 are each independently selected from the group consisting of C1-C6 alkyl, C1-C6 alkenyl, C1-C6 dienyl, C1-C6 trienyl, and C3-C8 cycloalkyl;
• wherein at least two of R1, R2, and R3 may be connected with the N+ to form a heterocyclic ring;
• and
• R4 is C1-C8 hydrocarbyl, and
• wherein the at least two compounds have at least one different R substituent.

A process for preparing a compound having the formula 1:

• wherein
• R is C3-C23 hydrocarbyl;
• R1 is C1-C8 hydrocarbyl;
• R2 and R3 are each independently selected from the group consisting of C1-C6 alkyl, C1-C6 alkenyl, C1-C6 dienyl, C1-C6 trienyl, and C3-C8 cycloalkyl;
• wherein at least two of R1, R2, and R3 may be connected with the N+ to form a heterocyclic ring;
• and
• R4 is C1-C8 hydrocarbyl,
• the process comprising:
• (a) contacting an acid or ester of formula 2 with a dialkylamino-alcohol of formula 3:
• in the presence of an enzyme at conditions effective to form an intermediate of formula 4:
• wherein R, R1, R2, and R3 are as defined above and R7 is hydrogen or C1-C6 alkyl;
• and
• (b) contacting the intermediate of formula 4 with a sulfonate alkylating agent at conditions effective to form the compound of formula 1.

A process for preparing a mixture comprising at least two compounds having the formula 1:

• wherein
• R is C3-C23 hydrocarbyl;
• R1 is C1-C8 hydrocarbyl;
• R2 and R3 are each independently selected from the group consisting of C1-C6 alkyl, C1-C6 alkenyl, C1-C6 dienyl, C1-C6 trienyl, and C3-C8 cycloalkyl;
• wherein at least two of R1, R2, and R3 may be connected with the N+ to form a heterocyclic ring;
• and
• R4 is C1-C8 hydrocarbyl, and
• wherein the at least two compounds have at least one different R substituent,
• the process comprising:
• (a) contacting a mixture comprising at least two acids or esters of formula 2 with a dialkylamino-alcohol of formula 3:
• in the presence of an enzyme at conditions effective to form at least two intermediates of formula 4:
• wherein
• R, R1, R2, and R3 are as defined above,
• R7 is hydrogen or C1-C6 alkyl,
• the at least two acids or esters of the formula 2 have different R substituents, and
• the at least two intermediates of the formula 4 have different R substituents;
• and
• (b) contacting the intermediates of the formula 4 with a sulfonate alkylating agent at conditions effective to form the mixture of at least two compounds of the formula 1.