A variety of oximes were synthesized from the corresponding alcohols, alkyl halides, or alkyl sulfonates without using external oxidants. With this simple two-step procedure involving substitution with readily available TsNHOTBS and subsequent treatment with CsF, a range of oximes were prepared including the ones hardly preparable with conventional procedures.

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Throw your hat in the ring: A highly diastereoselective synthesis of the ABC rings of (-)-norzoanthamine has been achieved starting from the (-)-Hajos-Parrish ketone (see scheme). Three asymmetric quaternary carbon centers on the C ring were constructed by a 1,4-addition, and an intramolecular Diels-Alder reaction provided a trans-decalin scaffold on the AB rings.

Hydroxylamine hydrochloride Tert ‐Butyldimethylsilylchloride Dimethyformamide Triethylamine p‐ Toluenesulfonyl chloride O ‐TBS ‐N ‐tosylhydroxylamanie Phosphine, triphenyl 4‐Benxyloxy‐2‐buten‐1‐ol DEAD Cesium fluoride

Ausgehend vom (−)‐Hajos‐Parrish‐Keton gelang eine hoch diastereoselektive Synthese des ABC‐Ringsystems von (−)‐Norzoanthamin (siehe Schema). Die drei quartären Kohlenstoffstereozentren am C‐Ring wurden durch eine 1,4‐Addition eingeführt, und eine intramolekulare Diels‐Alder‐Reaktion erzeugte das trans‐Decalin‐Gerüst für das AB‐Ringsystem.

Oximes. -Alkyl halides and sulfonates can also be transformed into oximes. -(KITAHARA, K.; TOMA, T.; SHIMOKAWA, J.; FUKUYAMA*, T.; Org. Lett. 10 (2008) 11, 2259-2261; Grad. Sch. Pharm. Sci., Univ. Tokyo, Bunkyo, Tokyo 113, Japan; Eng.) -Jannicke 41-057

Stereoselective Synthesis of Spirotryprostatin A. -The asymmetric total synthesis of spirotryprostatin A (I) is achieved by means of an intramolecular Heck reaction to control the stereochemistry of the quaternary spiro center. All of the newly created stereo centers are formed by taking advantage of the unique conformation of the diketopiperazine skeleton. -(KITAHARA, K.; SHIMOKAWA, J.; FUKUYAMA*, T.; Chem. Sci. 5 (2014) 3, 904-907, http://dx.

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