Enantioselective Organocatalytic Intramolecular Diels—Alder Reactions. The Asymmetric Synthesis of Solanapyrone D.

Abstract

General Information. Commercial reagents were purified prior to use following the guidelines of Perrin and Armarego.1 Organic solutions were concentrated under reduced pressure on a Buchi rotary evaporator. Chromatographic purification of products was accomplished using forced-flow chromatography on ICN 60 32-64 mesh silica gel 63 according to the method described by Still. ). Optical Rotations were recorded on a Jasco P-1010 polarimeter (WI lamp, 589 nm, 25°C). Mass spectra were obtained from the UC Irvine Mass Spectral Facility. Gas Chromatography was performed on Hewlett-Packard 5890A and 6890Series gas chromatographs equipped with a split-mode capillary injection system and flame ionization detectors using a Bodman Chiraldex Γ-TA (30 m x 0.25 mm) column,

A new era for organic synthesis—highlights of the recent progress

“…The first total synthesis (Scheme 2-6) of this compound was reported in 2006 by Lambert and Danishefsky [154]. The whole synthesis is extremely concise, with the critical retrosynthetic disconnection done right in the middle of the molecule between the two apparent fragments (one of the fragments was synthesized using McMillian et al's method [155]). …”

Directed Evolution: An Approach to Engineer Enzymes

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