A short stereoselective synthesis of (+)-(6R,2′S)-cryptocaryalactone via ring- closing metathesis

• Palakodety Radha Krishna,
• Krishnarao Lopinti and
• K. L. N. Reddy

Beilstein J. Org. Chem. 2009, 5, No. 14, doi:10.3762/bjoc.5.14

• : Carreira asymmetric alkynylation; Cryptocarya bourdilloni GAMB (Lauraceae); ring-closing metathesis; Sharpless asymmetric epoxidation; Introduction Natural products play an important role in the development of drugs and mankind has always taken advantage of nature as pharmacy: approximately 40% of the

• itself could be realised from the acryloylation of the corresponding homoallylic alcohol which in turn can be synthesized from 7. Chiral propargyl alcohol 7 was obtained by the Carreira asymmetric alkynylation reaction of the corresponding aldehyde, which was synthesized from the corresponding primary

• -mediated alkynylation conditions were examined to access the requisite propargyl alcohol 7 (Table 1). Amongst all of these, the Carreira asymmetric alkynylation gave excellent diastereomeric excess (>94% de) [40][41] and the propargyl alcohol 7 was obtained with the correct absolute configuration