Sorafenib, Busulfan and Fludarabine in Treating Patients With Recurrent or Refractory Acute Myeloid Leukemia Undergoing Donor Stem Cell Transplant

Inclusion Criteria: * Age \>= 18 and =\< 70 years * Patients with acute myeloid leukemia both flt3 positive and negative * Human leukocyte antigen (HLA)-identical sibling or 8/8 matched unrelated donor available * Life expectancy of at least 12 weeks (3 months) * Direct bilirubin =\< 1 mg/dL * Alanine transaminase (ALT) =\< 3 x upper limit of normal * Serum creatinine =\< 1.5 x the upper limit of normal * Creatinine clearance \>= 50 * Diffusing capacity for carbon monoxide (DLCO) \> 50% of predicted corrected for hemoglobin * Left ventricular ejection fraction (LVEF) \>= 50% * Subjects must be able to understand and be willing to sign the written informed consent form. A signed informed consent form must be appropriately obtained prior to the conduct of any trial-specific procedure * Women of childbearing potential must have a negative serum pregnancy test performed within 7 days prior to the start of study drug. Post-menopausal women (defined as no menses for at least 1 year) and surgically sterilized women are not required to undergo a pregnancy test * Subjects (men and women) of childbearing potential must agree to use adequate contraception beginning at the signing of the informed consent form (ICF) until at least 30 days after the last dose of study drug. The definition of adequate contraception will be based on the judgment of the principal investigator or a designated associate * Subject must be able to swallow and retain oral medication Exclusion Criteria: * Acute …