D-苯甘氨醇 、 2-氧代庚-6-烯酸乙酯 在
3 A molecular sieve 作用下,
以
various solvent(s) 为溶剂,
反应 0.75h,
以50%的产率得到(R)-3-(pent-4-enyl)-5-phenyl-5,6-dihydro-2H-1,4-oxazin-2-one
参考文献:
名称:
An Efficient Entry to Optically Active anti- and syn-β-Amino-α-trifluoromethyl Alcohols
摘要:
The reaction of chiral 5,6-dihydro-2H-1,4-oxazin-2-ones with TMSCF3 in the presence of a suitable activator leads to trifluoromethyl lactols, which can be selectively reduced to anti-beta-amino-alpha-trifluoromethyl alcohols. The corresponding syn diastereoisomers are obtained when the starting imines are reduced and the nitrogen atom is conveniently protected. In addition, a novel rearrangement of the CF3 group in the lactol intermediates has been observed. This represents a formal CF3 addition to the imine function in the starting substrates.
Diastereoselective Intramolecular Additions of Allyl- and Propargylsilanes to Iminium Ions: Synthesis of Cyclic and Bicyclic Quaternary Amino Acids
作者:Santos Fustero、Natalia Mateu、Antonio Simón-Fuentes、José Luis Aceña
DOI:10.1021/ol1010246
日期:2010.7.2
Chiral imino lactones derived from (R)-phenylglycinol containing an allyl- or propargyltrimethylsilyl group in the side chain readily cyclized in the presence of acidic reagents to afford spirocyclic compounds with high diastereoselectivity. Removal of the chiral auxiliary produced 2-substituted 1-aminocycloalkanecarboxylic acids, whereas further cyclizations by means of metathesis or hydroamination reactions led to bicyclic derivatives of pipecolic acid and proline.