7219-72-9Relevant academic research and scientific papers
Mild TiIII- and Mn/ZrIV-catalytic reductive coupling of allylic halides: Efficient synthesis of symmetric terpenes
Barrero, Alejandro F.,Herrador, M. Mar,Quilez Del Moral, Jose F.,Arteaga, Pilar,Arteaga, Jesus F.,Dieguez, Horacio R.,Sanchez, Elena M.
, p. 2988 - 2995 (2007/10/03)
(Chemical Equation Presented) Two new efficient methods for the regioselective homocoupling of allylic halides using either catalytic Ti III or the combination Mn/ZrIV catalyst have been developed. The regio- and stereoselectivity of the process proved to increase significantly when the Mn/ZrIV catalyst is used as the coupling reagent and when cyclic substituted allylic halides are used as substrates. The use of Lewis acids such as collidine hydrochloride allowed the quantity of catalyst to be lowered up to 0.05 equiv. We have proved the utility of these protocols with the synthesis of different terpenoids such as (+)-β-onoceradiene (1), (+)-β-onocerine (2), squalene (5), and advanced key-intermediates in the syntheses of (+)-cymbodiacetal (3) and dimeric ent-kauranoids as xindongnin M (4a).
Reductive coupling of terpenic allylic halides catalyzed by Cp 2TiCl: A short and efficient asymmetric synthesis of onocerane triterpenes
Barrero, Alejandro F.,Herrador, M. Mar,Del Moral, Jose F. Quilez,Arteaga, Pilar,Arteaga, Jesus F.,Piedra, Maria,Sanchez, Elena M.
, p. 2301 - 2304 (2007/10/03)
(Chemical Equation Presented) Titanocene chloride catalyzes the regioselective α,α′-homocoupling of terpenic allylic halides. This process has been employed in the short and effective synthesis of terpenoids such as β-onoceradiene (1), β-onocerin (2), and squalene (3). Evidence is presented for η1-allyltitanium species being involved in the coupling.
FERN CONSTITUENTS; ONOCEROID, α-ONOCERADIENE, SERRATENE AND ONOCERANOXIDE, ISOLATED FROM LEMMAPHYLLUM MICROPHYLLUM VARIETIES
Ageta, Hiroyuki,Shiojima, Kenji,Masuda, Kazuo
, p. 2272 - 2274 (2007/10/02)
α-Onoceradiene (I) and serratene (IV) were isolated and identified from a Polypodiaceous fern, Lemmaphyllum microphyllum var. microphyllum, while a new compound, onoceranoxide (VII), was obtained from var. obovatum as a main triterpenoid and its structure was established.Keywords-triterpenoid; onoceroid; α-onoceradiene; serratene; onoceranoxide; fern constituent; Lemmaphyllum microphyllum; Lemmaphyllum microphyllum var. obovatum
