Ray Stantz Ray Stantz Raymond "Ray" Stantz, PhD is a fictional character from the "Ghostbusters" franchise. He appears in the films "Ghostbusters" (1984), "Ghostbusters II" (1989), "Casper" (1995, as a cameo), the animated television series "The Real Ghostbusters" and "Extreme Ghostbusters", and the video games Beeline's "Ghostbusters" and "". He was portrayed by Dan Aykroyd in both live action films, and voiced by Frank Welker in the animated series. He is a member of the Ghostbusters and one of the three doctors of parapsychology, along with Dr. Peter Venkman and Dr. Egon Spengler. Dan Aykroyd has a cameo appearance in "Ghostbusters" (2016)
Pictet–Spengler reaction tetrahydroisoquinoline synthesis. Reaction conditions are generally harsher than the indole variant, and require refluxing conditions with strong acids like hydrochloric acid, trifluoroacetic acid or superacids. Instead of catalyzing the Pictet-Spengler cyclization with strong acid, one can acylate the iminium ion forming the intermediate "N"-acyliminium ion. The "N"-acyliminium ion is a very powerful electrophile and most aromatic ring systems will cyclize under mild conditions with good yields. Tadalafil is synthesized via the "N"-acyliminium Pictet–Spengler reaction. This reaction can also be catalyzed by AuCl and AgOTf. When the Pictet–Spengler reaction is performed with an aldehyde other than formaldehyde, a new chiral center