  Results are presented from a search for supersymmetry in events with a single
electron or muon and hadronic jets. The data correspond to a sample of
proton-proton collisions at $\sqrt{s} = $ 13 TeV with an integrated luminosity
of 35.9 fb$^{-1}$, recorded in 2016 by the CMS experiment. A number of
exclusive search regions are defined according to the number of jets, the
number of b-tagged jets, the scalar sum of the transverse momenta of the jets,
and the scalar sum of the missing transverse momentum and the transverse
momentum of the lepton. Standard model background events are reduced
significantly by requiring a large azimuthal angle between the direction of the
lepton and of the reconstructed W boson, computed under the hypothesis that all
of the missing transverse momentum in the event arises from a neutrino produced
in the leptonic decay of the W boson. The numbers of observed events are
consistent with the expectations from standard model processes, and the results
are used to set lower limits on supersymmetric particle masses in the context
of two simplified models of gluino pair production. In the first model, where
each gluino decays to a top quark-antiquark pair and a neutralino, gluino
masses up to 1.8 TeV are excluded at the 95% CL. The second model considers a
three-body decay to a light quark-antiquark pair and a chargino, which
subsequently decays to a W boson and a neutralino. In this model, gluinos are
excluded up to 1.9 TeV.
