Preparation of 4-((6BR,10AS)-3-methyl-2,3,6B,9,10, 10A-hexahydro-1H-pyrido[3′,4′:4,5]pyrrolo [1,2,3-de]quinoxalin-8-(7H)-yl)-1-(4-fluorophenyl)-1-butanone or a pharmaceutically acceptable salt thereof

1. A method for preparing a compound of Formula 2J:

or a pharmaceutically acceptable salt thereof, wherein:

(i) k is 1;

(ii) m is 1;

(iii) n is 1;

(iv) R 1 is 4-(4-fluorophenyl)-4-oxobutyl;

(v) R 5 is H;

(vi) R 6a and R 6b are H;

(vii) R 7 , R 8 and R 9 are H;

(viii) R 10 is —CH 3 ; and

(ix) X is N;

comprising the steps of:

a) deprotecting a compound of Formula 2H:

wherein:

(i) k is 1;

(ii) m is 1;

(iii) n is 1;

(iv) B is benzyl or triphenylmethyl; or

B is a compound of the Formula:

wherein:

(a) P is —C(O)—, —C(O)O— or —S(O) 2 —; and

(b) Z is C 1-6 alkyl, C 1-6 alkylaryl, aryl or —OR, where R is C 1-6 alkyl, aryl, arylC 1-6 alkyl or heteroarylC 1-6 alkyl;

(v) R 5 is H;

(vi) R 6a and R 6b are H;

(vii) R 7 , R 8 and R 9 are H;

(viii) R 10 is —CH 3 ; and

(ix) X is N;

to give a compound of Formula 2I:

wherein:

(i) k is 1;

(ii) m is 1;

(iii) n is 1;

(iv) R 5 is H;

(v) R 6a and R 6b are H;

(vi) R 7 , R 8 and R 9 are H;

(vii) R 10 is —CH 3 ; and

(viii) X is N;

b) alkylating the compound of Formula 2I:

wherein:

(i) k is 1;

(ii) m is 1;

(iii) n is 1;

(iv) R 5 is H;

(v) R 6a and R 6b are H;

(vi) R 7 , R 8 and R 9 are H;

(vii) R 10 is —CH 3 ; and

(viii) X is N;

with 4-chloro-4′-fluorobutyrophenone in the presence of a base to give the compound of Formula 2J; and

c) optionally reacting the compound of Formula 2J with an acid to give a pharmaceutically acceptable salt of the compound of Formula 2J.

2. The method according to claim 1 , wherein step a) comprises potassium hydroxide.

3. The method according to claim 1 , wherein the base is triethylamine.

4. The method according to claim 1 , wherein step b) further comprises sodium iodide or potassium iodide.

5. The method according to claim 1 , wherein the acid is toluenesulfonic acid.