file.copy

FSlash<- function(path = "clipboard") {
  y <- if (path == "clipboard") {
    readClipboard()
  } else {
    cat("Please enter the path:\n\n")
    readline()
  }
  x <- chartr("\\", "/", y)
  writeClipboard(x)
  return(x)
}

FSlash() -> NEED

dir(NEED) -> folder_names

dir.create("G:/temp_pdf")

for(i in folder_names){
  dir(paste0(NEED,"/",i)) -> folder_files
  if(length(folder_files) == 1) file.copy(from = paste0(NEED,"/",i,"/",folder_files),
                                          to = paste0("G:/temp_pdf/",folder_files))
}