Search results for "Crotyl"
showing 3 items of 3 documents
New and less known Orthoptera (Insecta) from the island of Socotra (Yemen)
2009
A list of nine species of Orthoptera collected on Socotra is reported. Three of them were previously unrecorded on the island (Trigonidium cicindeloides, Paratettix subpustulatus and Acrotylus insubricus) and one (Ochrilidia socotrae n.sp.) was undescribed. Further systematic notes on Glomeremus pileatus, G. mediopictus, Pyrgomorpha conica tereticornis, Acrotylus incarnatus and Sphingonotus insularis are included. The East African Acrotylus meruensis, previously considered synonym of A. incarnatus, is proposed as a valid species, distinct from the latter.
Relay Catalysis: Enantioselective Synthesis of Cyclic Benzo-Fused Homoallylic Alcohols by Chiral BrOnsted Acid-Catalyzed Allylboration/Ring Closing M…
2013
Six- and seven-membered benzo-fused cyclic homoallylic alcohols can be readily synthesized by a tandem chiral BrOnsted acid-catalyzed allyl (crotyl)boration/ring closing metathesis sequence performed under orthogonal relay catalysis conditions. Excellent enantio- and diastereoselectivities are obtained in most of the cases. In addition, the parent crotylboration/RCM process is also described. The required substrates, ortho-vinylbenzaldehydes, are readily available in one step from commercially available starting materials. Both catalysts and reactants are also available from commercial suppliers. The reaction shows broad functional group compatibility and is also suitable for heteroaromatic…
Titanium complexes for the formation of nitrogen compounds : synthesis of homoallylamines and amidines
2011
Homoallylic amines are key reagents for the formation of a large number of biologically interesting products. Due to the double bond of their allylic moiety, easily functionalisable, they are commonly used in organic synthesis. This research work deals with the synthesis of homoallylic amines thanks to titanium complexes. In fact, the reductive coupling between of imines and dienes promoted by titanium allows the formation of diastereoisomeric homoallylamines syn and anti. The diastereoselectivity of the reaction is directly affected by the nitrogen substituent. Whether it is benzyl or phenyl, the selectivity will be in favour of syn or anti respectively. Moreover, the addition of a the Lew…