Zur Photochemie von Δ1,9-10-Methyl-2-octalon

✍ Scribed by Paul Margaretha; Kurt Schaffner

• Publisher: John Wiley and Sons
• Year: 1973
• Tongue: German
• Weight: 289 KB
• Volume: 56
• Category: Article
• ISSN: 0018-019X
• DOI: 10.1002/hlca.19730560825

✦ Synopsis

Rf), [m]g = -173" (MeOH). MS. (both diastereomers) : M+ 353, base peak: 189. -I X (mixture of a and b) -t BrCN in abs. C,H, --f X. IR. (CHCI,) : 22OO/cm

. M S . : M+ : 378, dominating peaks 283 and 95. -X (4.6 x 1 0 -6 ~ in C,H,,, saturated with air) was irradiated (254 nm) -+ XI: m.p. 151-2'; UV.: Amax (log&): 257 (4.73), 285 (4.44), 311 (3.90), 342 (2.89), 3.59 nm (2.31); M e : 376: [a]g = + 74.7 (CHCI,). -X I + LiRlH, in THI7-i. XI1 (viscous oil). M + : 351, small intensity [7], dominating peaks 349, 282 and 70; [a]$ =+ 8.1". -XI1 + 98% HCOOH/lSOo + XIII; cyclisation (without further purification) with POCl,/toluene+ XIV; UV.: Amax: 259; 268; 282; 320; 420 nm. XIV + NaBH,/MeOH + XV, m.p. 206-11".

[m]g =+ 66" (CHC13): antofine: [m]g = -131" (CHC1,). XV was identical with natural antofine [8] (TLC., UV., MS., IR.) but shows opposite optical rotation, 50% in magnitude for the reason stated. Becausc XV has S-configuration, antofine is of the R-configuration. This is in accord with our degradation of antofine to D-proline ~91.