58542-75-9Relevant academic research and scientific papers
Total synthesis of (+)-dactylol via a novel [3 + 5] annulation approach
Molander,Eastwood
, p. 4559 - 4565 (1995)
(+)-Dactylol (1) has been synthesized from the known (R)-3-methyl-2-methylenecyclopentanone (20) in six steps. The key step in the synthesis involves a regioselective and stereoselective [3 + 5] annulation to afford a tricyclic ether, which upon suitable functional group manipulation was opened to provide the natural product.
Chemical conversion of humulene to dactylol. Biomimetic, apparent 1,2-shift of a methyl group
Hayasaka, Kazuhiro,Ohtsuka, Toshikazu,Shirahama, Haruhisa,Matsumoto, Takeshi
, p. 873 - 876 (1985)
Africanol, which had been previously derived from humulene, was converted to dactylol through a formal 1,2-shift of a methyl group, which involved a cyclopropane sliding reaction and subsequent cyclopropane ring opening.
Intramolecular 4 + 3 cycloadditions. Aspects of stereocontrol in the synthesis of cyclooctanoids. A synthesis of (+)-dactylol
Harmata, Michael,Rashatasakhon, Paitoon
, p. 2913 - 2915 (2000)
The judicious placement of stereocenters on precursors for 4 + 3 cycloaddition reactions can lead to high levels of stereocontrol in the 4 + 3 cycloaddition process of cyclopentenyl cations and tethered butadienes. This concept was successfully tested in the context of a synthesis of (+)-dactylol.
Ring-closing metathesis of allylsilanes as a flexible strategy toward cyclic terpenes. Short syntheses of teucladiol, isoteucladiol, poitediol, and dactylol and an attempted synthesis of caryophyllene
Dowling, Matthew S.,Vanderwal, Christopher D.
experimental part, p. 6908 - 6922 (2010/11/24)
The development of a strategy consisting of allylsilane ring-closing metathesis and subsequent SE′ electrophilic desilylation (allylsilane RCM/SE′) to construct exo-methylidenecycloalkanes is described. Its utility is documented in short syntheses of teucladiol and poitediol. A key transformation in the synthesis of teucladiol is an aldol addition that establishes three stereochemical relationships in one step with ≥10:1 diastereoselectivity and provides a fascinating example of double stereodifferentiation/kinetic resolution with racemic reaction partners in the context of natural product synthesis. The synthesis of (±)-teucladiol required five steps from cyclopentenone and proceeded in 28% overall yield; adaptation of this route to an enantioselective synthesis of (-)-teucladiol enabled the determination of the absolute configuration of this terpene natural product. The use of fluoride-mediated conditions in the final desilylation step preserves the location of the alkene, delivering the natural product (±)-isoteucladiol (five steps and 21% yield from cyclopentenone). The synthesis of poitediol showcases the power of RCM for constructing eight-membered rings and features a highly diastereoselective epoxidation/fluoride-mediated fragmentation sequence for installing the exo-methylidene group with an adjacent hydroxyl-bearing stereocenter. The synthesis of (±)-poitediol required seven steps and proceeded in 18% overall yield. Again, fluoride-mediated desilylation of a late-stage intermediate (with retention of double-bond location) delivered the natural product (±)-dactylol (seven steps and 24% yield). Efforts directed toward incorporating the RCM/SE′ sequence into a synthesis of caryophyllene are also disclosed. While ultimately unsuccessful, these efforts resulted in the identification of a novel metal alkylidene-promoted deallylation reaction of terminal 1,4-dienes. A possible mechanism for this unexpected deallylation reaction of 1,4-dienes is provided.
Intramolecular [4 + 3] cycloadditions - Stereochemical issues in the cycloaddition reactions of cyclopentenyl cations - A synthesis of (+)-dactylol
Harmata, Michael,Rashatasakhon, Paitoon,Barnes, Charles L.
, p. 1456 - 1469 (2007/10/03)
Five cyclopentanones were prepared for the purpose of examining the effects of stereogenic centers on the course of the intramolecular [4 + 3] cycloaddition reactions of cyclopentenyl cations. One substrate reacted with very high levels of diastereoselect
A concise total synthesis of dactylol via ring closing metathesis
Fuerstner, Alois,Langemann, Klaus
, p. 8746 - 8749 (2007/10/03)
A straightforward total synthesis of the cyclooctenoid sesquiterpene dactylol (1) and of 3a-epi-dactylol (13) has been achieved in six synthetic operations. The unusual rearranged bicyclo[6.3.0]undecane isoprenoid skeleton of these target molecules has been formed via an initial three component coupling triggered by 1,4-addition of a methylcopper reagent (MeLi, CuI, Bu3P) to cyclopentenone, followed by trapping of the enolate formed with 2,2-dimethyl-4-pentenal as the electrophile. The aldol 8 thus obtained was elaborated into the trans-disubstituted cyclopentanone derivative 10 which reacted with a methallylcerium reagent to afford a mixture of the tertiary alcohols 11a and 12a. Separation and O-silylation of these diastereoisomers, ring-closing metathesis (RCM) of the resulting dienes 11b and 12b to form the cyclooctene ring using Schrocks molybdenum carbene 5 as a precatalyst, and a final deprotection afforded the title compound and its epimer in excellent yields. This approach clearly surpasses previous ones in terms of efficiency, flexibility, accessibility of the substrates, number of steps, atom economy, and overall yield.
Total synthesis of (±)-dactylol and related studies
Feldman, Ken S.,Wu, Ming-Jung,Rotella, David P.
, p. 8490 - 8496 (2007/10/02)
The marine sesquiterpene (±)-dactylol was prepared from 2,5-dimethyl-7-(3-methyl-4-pentenyl)tropone in six steps. Salient features of the synthesis include: (1) a stereo- and regioselective intramolecular tropone-alkene [6π + 2π] photocyclization to furni
Stereoelectronic Effects in Cyclo-octanes: Synthesis of (+/-)-Dactylol and (+/-)-Isodactylol
Gadwood, Robert C.
, p. 123 - 124 (2007/10/02)
Racemic dactylol and isodactylol were synthesized from racemic poitediol and 4-epipoitediol respectively.
