Process for preparing an alkoxymethyl alkynyl ether compound having a terminal triple bond

A process for preparing an alkoxymethyl alkynyl ether compound having a terminal triple bond of the following formula (4):

• H—C≡C(CH2)aOCH2OCH2R (4)
• wherein R represents a hydrogen atom, an n-alkyl group having 1 to 9 carbon atoms, or a phenyl group, and “a” represents an integer of 1 to 10, the method comprising:
• subjecting an alkynol compound having a terminal triple bond of the following formula (1):
• H—C≡C(CH2)aOH (1)
• wherein a is as defined above,
• to an alkoxymethylation with a halomethyl alkyl ether compound of the following formula (3):
• RCH2OCH2X (3)
• wherein X represents a halogen atom, and R is as defined above,
• in the presence of a dialkylaniline compound of the following formula (2) as a base:
• [CH3(CH2)b][CH3(CH2)c]NC6H5 (2)
• wherein b and c represent, independently of each other, an integer of 0 to 9,
• to form the alkoxymethyl alkynyl ether compound (4) having a terminal triple bond,
• wherein:
• (i) the alkoxymethylation is carried out without any additional solvent other than the dialkylaniline compound (2), or
• (ii) the method further comprises a post-treatment that is carried out by subjecting a reaction mixture comprising the alkoxymethyl alkynyl ether compound (4) to a neutralization with a base other than the dialkylaniline compound (2) in the presence of water, or
• (iii) the alkoxymethylation is carried out without any additional solvent other than the dialkylaniline compound (2), and the method further comprises a post-treatment that is carried out by subjecting a reaction mixture comprising the alkoxymethyl alkynyl ether compound (4) to a neutralization with a base other than the dialkylaniline compound (2) in the presence of water.