Polymerizable polar compound, liquid crystal composition, and liquid crystal display element

A compound, represented by formula (1):

• wherein, in formula (1),
• R1 is alkyl having 1 to 15 carbons, and in the alkyl, at least one —CH2— may be replaced by —O— or —S—, and at least one piece of —(CH2)2— may be replaced by —CH═CH— or —C≡C, and in the groups, at least one hydrogen may be replaced by halogen;
• MES is a mesogen group having at least one ring;
• Sp1 is a single bond or alkylene having 1 to 10 carbons, and in the alkylene, at least one —CH2— may be replaced by —O—, —CO—, —COO—, —OCO— or —OCOO—, and at least one (CH2)2— may be replaced by —CH═CH— or —C≡C—, and in the groups, at least one hydrogen may be replaced by halogen;
• M1 and M2 are independently hydrogen, halogen, alkyl having 1 to 5 carbons, or alkyl having 1 to 5 carbons in which at least one hydrogen is replaced by halogen;
• and
• R2 is a group represented by formula (1a), formula (1b) or formula (1c):
• wherein, in formula (1a), formula (1b) and formula (1c),
• Sp2 and Sp3 are independently a single bond or alkylene having 1 to 10 carbons, and in the alkylene, at least one —CH2— may be replaced by —O—, —NH—, —CO—, —COO—, —OCO— or —OCOO—, and at least one —(CH2)2— may be replaced by —CH═CH— or —C≡C— and in the groups, at least one hydrogen may be replaced by halogen;
• S1 is >CH— or >N—;
• S2 is >C< or >Si<;
• and
• X1 is a group represented by —OH, —NH2, —OR3, —N(R3)2, formula (x1), —COOH, —SH, —B(OH)2 or —Si(R3)3, in which R3 is hydrogen or alkyl having 1 to 10 carbons, and in the alkyl, at least one CH2— may be replaced by —O—, and at least one —(CH2)2— may be replaced by —CH═CH—, and in the groups, at least one hydrogen may be replaced by halogen, and w in formula (x1) is 1, 2, 3 or 4: