A process for preparation of 4-Methylene tetrahydrofuran compound of formula II comprising one or more of the following steps: wherein P 1 is H or an alcohol protecting group; P 2 is H or an alcohol protecting group or -SO 2 (R 1); wherein R 1 is selected from straight or branched C 1- C 10 alkyl or optionally substituted C 5 -C 12 aryl; X is halogen; (a) reacting compound of formula III with compound of formula XIII to provide compound of formula XIV; wherein P is an alcohol-protecting group; R 2, R 3 is same or different and are independently selected from hydrogen, alkyl, alkenyl, alkoxy, heteroalkyl, aryl, aralkyl, heteroaryl; all optionally substituted through available carbon atoms with 1, 2, 3, 4 or 5 groups selected from hydrogen, halo, alkyl, alkoxy, haloalkoxy, alkenyl, alkynyl, cycloalkyl, heteroalkyl, aryl, nitro, cyano, amino or substituted amino and the like or R 2 and R 3 together to form a 4-7 membered ring containing a 1-3 heteroatoms selected from N, O, S wherein one or more carbon or hetero atoms of the 4-7 membered ring optionally substituted with halo, alkyl, alkoxy, carbonyl, thiocarbonyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, heteroalkyl, aryl, nitro, cyano or amino; provided that when R 2 is methyl, then R 3 is not methoxy or when R 3 is methyl, then R 2 is not methoxy. For example, -NR 2 R 3 include; or stereoisomers thereof; (b) protecting compound of formula XIV to provide compound of formula XV; wherein P, R 2 and R 3 are as defined above; (c) deprotecting compound of formula XV to provide compound of formula XVI; wherein P, R 2 and R 3 are as defined above; (d) converting compound of formula XVI to provide compound of formula XVII; wherein P, R 2 and R 3 are as defined above; (e) reacting compound of formula XVII with compound of formula IX to provide compound of formula XVIII; wherein P is an alcohol-protecting group; LG is -OSO 2 (R 1); wherein R 1 is selected from straight or branched C 1- C 10 alkyl or optionally substituted C 5 -C 12 aryl; X is halogen and R 2 and R 3 as defined above; (f) converting compound of formula XVIII to compound of formula XI; and wherein P is an alcohol-protecting group; (g) converting compound of formula XI to compound of formula II. (a) reacting compound of formula III with compound of formula XIII to provide compound of formula XIV; wherein P is an alcohol-protecting group; R 2, R 3 is same or different and are independently selected from hydrogen, alkyl, alkenyl, alkoxy, heteroalkyl, aryl, aralkyl, heteroaryl; all optionally substituted through available carbon atoms with 1, 2, 3, 4 or 5 groups selected from hydrogen, halo, alkyl, alkoxy, haloalkoxy, alkenyl, alkynyl, cycloalkyl, heteroalkyl, aryl, nitro, cyano, amino or substituted amino and the like or R 2 and R 3 together to form a 4-7 membered ring containing a 1-3 heteroatoms selected from N, O, S wherein one or more carbon or hetero atoms of the 4-7 membered ring optionally substituted with halo, alkyl, alkoxy, carbonyl, thiocarbonyl, haloalkoxy, alkenyl, alkynyl, cycloalkyl, heteroalkyl, aryl, nitro, cyano or amino; provided that when R 2 is methyl, then R 3 is not methoxy or when R 3 is methyl, then R 2 is not methoxy. For example, -NR 2 R 3 include; or stereoisomers thereof; (b) protecting compound of formula XIV to provide compound of formula XV; wherein P, R 2 and R 3 are as defined above; (c) deprotecting compound of formula XV to provide compound of formula XVI; wherein P, R 2 and R 3 are as defined above; (d) converting compound of formula XVI to provide compound of formula XVII; wherein P, R 2 and R 3 are as defined above; (e) reacting compound of formula XVII with compound of formula IX to provide compound of formula XVIII; wherein P is an alcohol-protecting group; LG is -OSO 2 (R 1); wherein R 1 is selected from straight or branched C 1- C 10 alkyl or optionally substituted C 5 -C 12 aryl; X is halogen and R 2 and R 3 as defined above; (f) converting compound of formula XVIII to compound of formula XI; and wherein P is an alcohol-protecting group; (g) converting compound of formula XI to compound of formula II.