Three Wide-Separation L dwarf Companions from the Two Micron All Sky Survey: Gl 337C, Gl 618.1B, and HD 89744B

We present two confirmed wide separation L-dwarf common proper motion companions to nearby stars and one candidate identified from the Two Micron All Sky Survey. Spectral types from optical spectroscopy are L0 V, L2.5 V, and L8 V. Near-infrared low resolution spectra of the companions are provided as well as a grid of known objects spanning M6 V -- T dwarfs to support spectral type assignment for these and future L-dwarfs in the z'JHK bands. Using published measurements, we estimate ages of the companions from physical properties of the primaries. These crude ages allow us to estimate companion masses using theoretical low-mass star and brown dwarf evolutionary models. The new L-dwarfs in this paper bring the number of known wide-binary (Separation >= 100 AU) L-dwarf companions of nearby stars to nine. One of the L-dwarfs is a wide separation companion to the F7 IV-V + extrasolar planet system HD89744Ab.