how to filter data in array loop

In my array is like this,

var myColumnDefs = [

    {a: "hh", b: "hh", c: "jk", d: "ggh", e: "hvh"},

    {a: "dd", b: "gg", d: "nn", e: "rr", f: "jj"},.....
]

I want to filter data and insert data in new array like this

var newarray = {a,b,c,d,e,f}

& another array

var mysecondarray = [

                {hh,hhjk,ggh,hvh},

                {dd,gg,nm,rr,jj},....
]