2-methylhexanoyl-CoA + oxidized [electron-transfer flavoprotein] + H(+) => 2-methylhexenoyl-CoA + reduced [electron-transfer flavoprotein]
2-methylhexanoyl-coa + oxidized [electron-transfer flavoprotein] + h(+) => 2-methylhexenoyl-coa + reduced [electron-transfer flavoprotein]