Translite

gulpfile.js

var gulp     = require('gulp'),
    path     = require('path'),
    rename   = require('gulp-rename'),
    translit = require('translitit-cyrillic-russian-to-latin');

gulp.task('files', function () {
    gulp.src('./файл.txt')
        .pipe(rename(function (path) {
            path.basename = translit(path.basename);
        }))
        .pipe(gulp.dest('./dest/'));
});

gulp.task('default', ['files']);