... After filtration of the catalyst, the benzaldehydes were isolated in 70-75% yield by careful fractionation through a 10-plates vacuum-shielded Oldershaw column. ... (16) “Organic Syntheses”, coll. vol. I, p. 78, J. Wiley, New York (NY) 1941. ... SOC. Chim. Belges, 70, 77 (1961). ...