Process of a quaternary ammonium salt

A process for preparing a compound of formula (8):

• or an acid addition salt thereof
• wherein
• B is a carbonyl group or a sulfonyl group,
• R5a, R5b, R5c, and R5d are independently hydrogen atom or C1-4 alkyl group, alternatively R5a and R5b, or R5a and R5c may be taken together to form a hydrocarbon ring, or R5a and R5c may be taken together to form an aromatic hydrocarbon ring, wherein the hydrocarbon ring may be bridged with C1-4 alkylene or oxygen atom wherein the C1-4 alkylene and the hydrocarbon ring may be substituted with at least one C1-4 alkyl,
• q is 0 or 1, and
• Y is a substituent of the following formula (2a) or (2b):
• wherein R1 is independently methylene or oxygen atom;
• R2 is independently C1-6 alkyl group, C1-6 alkoxy group, or hydroxy group;
• m and n are independently 0, 1, 2, or 3;
• and p is 1 or 2, and
• Z is =N-R3 or =CH-R4 wherein R3 is C1-6 alkyl group, C3-7 cycloalkyl group, C5-7 cycloalkenyl group, C6-10 aryl group, or 5- to 10-membered monocyclic or bicyclic heteroaryl group;
• R4 is C1-6 alkyl group, C1-6 alkoxy group, C1-6 alkylthio group, C3-7 cycloalkyl group, C3-7 cycloalkyloxy group, C3-7 cycloalkylthio group, C5-7 cycloalkenyl group, C5-7 cycloalkenyloxy group, C5-7 cycloalkenylthio group, C6-10 aryl group, C6-10 aryloxy group, C6-10 arylthio group, 5- to 10-membered monocyclic or bicyclic heteroaryl group, 5- to 10-membered monocyclic or bicyclic heteroaryloxy group, or 5- to 10-membered monocyclic or bicyclic heteroarylthio group,
• comprising the following steps (i) and (ii):
• step (i)
• a process for preparing a quaternary ammonium salt of formula (4):
• wherein X is halogen atom, C1-6 alkylsulfonyloxy group, or C6-10 arylsulfonyloxy group, and Y and Z are as defined above,
• comprising reacting a compound of formula (1):
• wherein X and Y are as defined above,
• with 1.8 to 15 mole of a compound of formula (3):
• wherein Z is as defined above, per one mole of the compound of formula (1)
• to prepare the quaternary ammonium salt of formula (4);
• and
• step (ii)
• a process for preparing the compound of formula (8):
• comprising reacting the quaternary ammonium salt (4) prepared in step (i) with the following compound (7):
• wherein B, R5a, R5b, R5c, R5d, and q are as defined above, in the presence of a solid inorganic base.