Topic
Alpine borane
About: Alpine borane is a research topic. Over the lifetime, 11 publications have been published within this topic receiving 196 citations.
Papers
TL;DR: An enantioselective total synthesis of (−)-chlorothricolide (1) has been completed via a route involving the tandem inter- and intramolecular Diels−Alder (IMDA) reaction of hexaenoate 19 and the chiral dienophile (R)-12 as mentioned in this paper.
Abstract: An enantioselective total synthesis of (−)-chlorothricolide (1) has been completed via a route involving the tandem inter- and intramolecular Diels−Alder (IMDA) reaction of hexaenoate 19 and the chiral dienophile (R)-12. This reaction, which establishes seven asymmetric centers in a single operation, is feasible only by virtue of the high diastereofacial and exo selectivity of dienophile 12. The C(9)-trimethylsilyl steric directing group of 19 also plays a key role by controlling the stereochemical course of the IMDA reaction leading to the bottom half octahydronaphthalene unit. Hexaenoate 19 was prepared in 32% overall yield by a 10-step sequence starting from the known acetylenic ketone 33. Key steps include the asymmetric reduction of 33 using Alpine Borane (up to 94% ee), the Suzuki cross coupling of α-iodo vinylsilane 20 with vinylboronic acid 21, and the Horner-type olefination of aldehyde 41 with dienylic phosphonate 22. The key tandem inter-intramolecular Diels−Alder reaction was performed by heat...
113 citations
TL;DR: Reduction de derives du benzeneglyoxylonitrile and de loxo-2 caprylonitrile in les ethanolamines correspondantes as discussed by the authors, a.k.a.
Abstract: Reduction de derives du benzeneglyoxylonitrile et de l'oxo-2 caprylonitrile en les ethanolamines correspondantes
23 citations
TL;DR: In this paper, the authors show that the reaction of benzaldehyde-1-d with B-Ipc-9-BBN involves a different conformation of the reagent and it does not proceed, as previously assumed, through a boat-like transition state.
Abstract: The results from this study show that, contrary to the accepted mechanism, the reaction of benzaldehyde-1-d with B-Ipc-9-BBN involves a different conformation of the reagent and it does not proceed, as previously assumed, through a boat-like transition state. The overall reactivity of the B-alkyl-9-BBN reagents is determined by the ability of the boron center to undergo efficient coordination expansion during the formation of the charge-dipole complex with benzaldehyde. The exclusive preference toward the (S)-benzyl-1-d alcohol in the reduction of benzaldehyde-1-d with B-Ipc-9-BBN is governed, also at the charge-complex stage, by preferential orientation of the benzaldehyde's C−D rather than C−Ph bond against one of the prostereogenic B−CH bonds of the 9-BBN moiety that is “gauche” to the C1−C2 bond of the Ipc ring.
8 citations
TL;DR: The first stereoselective total synthesis of nonenolide (−)-stagonolide D has been accomplished in this paper, where Midland Alpine borane reduction, Henbest epoxidation, Yamaguchi esterification and Olefin metathesis reaction are the key steps involved in the total synthesis.
6 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2017 | 1 |
| 2000 | 1 |
| 1998 | 2 |
| 1996 | 1 |
| 1991 | 1 |
| 1990 | 1 |