This is an investigational study. Sorafenib is FDA approved and commercially available for the treatment of metastatic renal cancer only. Idarubicin is FDA approved for use in combination with other approved antileukemic drugs for the treatment of acute myeloid leukemia (AML) in adults. Cytarabine is FDA approved for use in the treatment of leukemia. The use of sorafenib combined with idarubicin and Ara-C in the treatment of AML and high-risk MDS is investigational and authorized for use in research only. Up to 75 patients will take part in this study. All patients will be enrolled at M. D. Anderson Cancer Center.