Process to prepare oxazolidinones

A novel process for preparing a compound of formula I

• or a salt thereof, which comprises reacting a N-aryl —O-alkylcarbamate of formula II
• or a salt thereof, with a compound of formula III
• or a salt thereof, in the presence of a lithium cation, a base and a nucleophile, wherein
• X and Y are independently H or F;
• W1 is Cl, Br, or —OS(O)2—R;
• W2 is H or —C(O)—R1;
• R is aryl or alkyl, the alkyl optionally being substituted by one or more F, Cl, Br, or I;
• R1 is CH3, optionally substituted by one to three fluorine or chlorine atoms;
• R2 is cycloalkyl, phenyl, —CH2-phenyl, C2-6alkenyl, or C1-12alkyl optionally substituted by one to three of F, Br, Cl, —O—C1-6alkyl, and NR2aR2b;
• Each R2a and R2B is independently H or C1-4alkyl;
• Q is structure ii:
• Z2 is S, SO, SO2, O, or N(R);
• R6 is
• a) H,
• b) C1-6alkyl, optionally substituted with one or more OH, CN, or halo,
• c) —(CH2)h-aryl,
• d) —COR11,
• e) —COOR12,
• f) —CO—CH2)h—COR11,
• g) —SO2—C1-6alkyl,
• h) —SO2—(CH2)h-aryl, or
• i) —(CO)i-het;
• R12 is
• a) H,
• b) C1-6 alkyl, optionally substituted with one or more OH, CN, or halo,
• c) —(CH2)h-aryl, or
• d) —(CH2)h—OR13;
• R12 is
• a) C1-6 alkyl, optionally substituted with one or more OH, CN, or halo,
• b) —(CH2)h-aryl, or
• c) —(CH2)h—OR13;
• R13 is
• a) H,
• b) C1-6alkyl,
• c) —(CH2)h-aryl, or
• d) —CO(C1-6alkyl);
• aryl is phenyl, pyridyl or napthyl;
• at each occurance, aryl or phenyl may be optionally substituted with one or more F, Cl, Br, I, CN, OH,
• SH, C1-6 alkyl, OC1-6 alkyl, or SC1-6 alkyl, or OC(O)CH3;
• het is 5- to 10-membered heterocyclic rings having one or more oxygen, nitrogen, and sulfur atoms;
• his 1,2,3, or 4;
• i is 0 or 1;
• and
• m is 0 or 1.