Liquid crystal compound having a 3,6-dihydro-2H-pyran ring, negative dielectric anisotropy, liquid crystal composition and liquid crystal display device

A liquid crystal composition containing at least one compound represented by formula (1) and at least one compound represented by formula (2), (3) or (4)

• wherein, in formula (1),
• Ra and Rb are independently hydrogen or alkyl having 1 to 10 carbons, and in the alkyl, at least one —CH2— may be replaced by —O—, —S—, —CO— or —SiH2—, at least one —CH2CH2— may be replaced by —CH═CH— or —C≡C—, and in the groups, at least one hydrogen may be replaced by fluorine or chlorine, and Rb may be fluorine, chlorine, —C≡N or —C═C—C≡N;
• ring A1, ring A2 and ring A3 are independently 1,4-cyclohexylene, decahydronaphthalene-2,6-diyl, 1,4-phenylene, and in the groups, at least one —CH2— may be replaced by —O—, —S—, —CO— or —SiH2—, at least one —CH2CH2— may be replaced by —CH═CH— or —CH═N—, and in the divalent groups, at least one hydrogen may be replaced by fluorine, chlorine, —C≡N, —CF3, —CHF2, —CH2F, —OCF3, —OCHF2 or —OCH2F;
• ring N1 is 1,4-cyclohexylene, decahydronaphthalene-2,6-diyl, 1,2,3,4-tetrahydronaphthalene-2,6-diyl, 2,6,7-trioxabicyclo[2.2.2]octane-1,4-diyl, 1,4-phenylene, naphthalene-2,6-diyl, 9,10-dihydrophenanthrene-2,7-diyl, 9H-xanthene-2,6-diyl or 9H-fluorene-2,7-diyl, and in the groups, at least one —CH2— may be replaced by —O—, —S—, —CO— or —SiH2—, at least one —CH2CH2— may be replaced by —CH═CH— or —CH═N—, and in the divalent groups, at least one hydrogen may be replaced by fluorine, chlorine, —C≡N;
• —CF3, —CHF2, —CH2F, —OCF3, —OCHF2 or —OCH2F;
• G is a divalent group represented by formula (pr-1) or (pr-2);
• wherein,
• Z1 and Z2 are independently a single bond or alkylene having 1 to 6 carbons, and in the alkylene, at least one —CH2— may be replaced by —O—, —S—, —CO— or —SiH2—, one or two pieces of —CH2CH2— may be replaced by —C≡C—, and in the divalent groups, at least one hydrogen may be replaced by fluorine or chlorine;
• Z3 and Z4 are independently a single bond or alkylene having 1 to 6 carbons, and in the alkylene, at least one —CH2— may be replaced by —O—, —S—, —CO— or —SiH2—, one or two —CH2CH2— may be replaced by —CH═CH— or —C≡C—, and in the divalent groups, at least one hydrogen may be replaced by fluorine or chlorine;
• and
• a, b and c are independently 0, 1 or 2, and a sum of a, b and c is an integer from 0 to 3;
• and
• wherein, in formulas (2) to (4),
• R11 and R12 are independently alkyl having 1 to 10 carbons or alkenyl having 2 to 10 carbons, and in the alkyl and the alkenyl, at least one —CH2— may be replaced by —O—, and in the groups, at least one hydrogen may be replaced by fluorine;
• ring B1, ring B2, ring B3 and ring B4 are independently 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,5-difluoro-1,4-phenylene or pyrimidine-2,5-diyl;
• and
• Z11, Z12 and Z13 are independently a single bond, —COO—, —CH2CH2—, —CH═CH— or —C≡C—.