Note: There where not any papers cited relating to my step, so I found a paper about the ring opening that occurs when 23 is formed.
Paper Being Cited:
Jiang, L.; Chan, T.-H. Tetrahedron Lett. 1998, 39, 355-358.
First Paper Citing
Liu, L.; Pohl, N. Org. Lett. 2011, xx, 000-000
Second Paper Citing
Rao, K.; Patil, P.; Atmakuri, S; Kartha, K. P. Carbohydrate Research. 2011, 345, 2709-2713.
This is high yield reductive ring opening that uses slightly different reagents however the key component (BH3) is still present.