3-Methyl-2-pentanone (methyl sec-butyl ketone) is an aliphatic ketone and isomer of 2-hexanone. It is used as a solvent and as an intermediate for syntheses. Its industrial importance is low. It is produced by base-catalyzed aldol condensation of 2-butanone with acetaldehyde, forming 4-hydroxy-3-methyl-2-pentanone, which is dehydrated to 3-methyl-3-penten-2-one over an acid catalyst, followed by hydrogenation over a palladium catalyst.

CAS：565-61-7
中文别名：甲基仲丁基酮;
英文别名：3-methylpentan-2-one;
分子式：C6H12O
分子量：100.159
精确质量：100.089
Psa：17.07
Logp：1.6215

EINECS号：209-282-1
MDL号：MFCD00009336

外观与性状：无色至略黄色液体
密度：0.815g/mLat 25°C(lit.)
沸点：118°C758mm Hg(lit.)
闪点：54°F
折射率：n20/D 1.4(lit.)
储存条件：库房通风低温干燥,与氧化剂、酸类分开存放

安全说明：S16-S29-S33
WGK Germany：3
危险类别码：R11
海关编码：2914190090
危险品运输编码：UN 1224 3/PG 2
危险类别：3
包装等级：II
危险品标志：F

用途
用于有机合成。