Tetrahydropyranylation of Alcohols Under Solvent-Free Conditions

Figures & data

Scheme 1 Tetrahydropyranylation of alcohols.

Table 1. Conversion of benzyl alcohol to the corresponding THP ether under different conditions in the presence of pyridinium chloride

Entry	Solvent	Yield (%) ^b	Time (min)
1a	Dichloromethane ^a	80	45
1b	Acetonitrile ^a	80	15
1c	Ethyl acetate ^a	60	60
1d	Diethyl ether ^a	No reaction	60
1e	Cyclohexane ^a	70	30
1f	Solvent-free conditions	81	3

Table 2. Tetrahydropyranylation of alcohols using pyridinium chloride at room temperature under solvent-free conditions ^a

Entry	Substrate	Subst./DHP	Time (min)	Yield (%)
2a	PhCH2OH	1:1.2	3	80
2b	3-MeOC6H4CH2OH	1:1.2	2	90
2c	4-MeOC6H4CH2OH	1:1.2	3	80
2d	3,4-(MeO)2C6H4CH2OH	1:1.2	3	80
2e	2-MeOC6H4CH2OH	1:1.5	2	90
2f	2-ClC6H4CH2OH	1:1.3	3	80
2g	4-ClC6H4CH2OH	1:1.3	3	85
2h	3-ClC6H4CH2OH	1:1.5	2	90
2i	4-MeC6H4CH2OH	1:1.5	2	95
2j	3-NO2C6H4CH2OH	1:1.5	4	75
2k	4-NO2C6H4CH2OH	1:1.5	4	75
2l	PhCHOHPh	1:1.2	4	60
2m	PhCHOHMe	1:1.5	4	70
2n	PhC=CHCH2OH	1:1.5	3	80
2o	Ph(CH2)2OH	1:1.2	5	80
2p	Ph(CH2)4OH	1:1.2	5	90
2q		1:1.2	4	90
2r		1:1.2	3	83

short-legendScheme 2