H4 stamping & H4 to H1 COS


Currently i am having a valid H1 B till 2017. My spouse’s H1 picked up lottery this year & she is in India currently. Her H1 B is in RFE now. I am planning to send her for H4 stamping in a week & bring her to USA after the her H1 is completely approved. Can she travel to USA on H4 after her H1 is approved, once she reaches USA can she apply for COS for H4 to H1 so that she can start working in USA with H1 B VISA stamped ?

Thanks in Advance !!!