The gas phase kinetics of CH3CCCH2 radical reactions with NO and NO2 have been studied in direct time-resolved measurements using temperature controlled flow tube reactors coupled to a laser photolysis/photoionization mass spectrometer. Rate coefficients of both reactions were observed to display negative temperature dependence which for the NO2 reaction can be represented with k (CH3CCCH2 + NO2) = (3.97 +/- 0.10) x 10(-11) x (T/300 K)(-1.43 +/- 0.12) cm(3) s(-1) (221-363 K). The bath gas pressure dependence observed in the NO reaction required a pressure falloff parameterization to express the obtained rate coefficients (273-363 K). The association product C4H5NO was directly observed in the NO reaction and a product with a formula C4H5O was recorded in the NO2 reaction. (C) 2012 Elsevier B.V. All rights reserved.