Pheromone pine sawfly

Kallmerten et al. used iterative glycolate Claisen rearrangements to establish the three stereocenters in pine sawfly pheromone (Scheme 4.126) [120]. An initial Ire-land-Claisen reanangement of the Z-allylic alkene afforded the anti pentenoic... 

An iterative Claisen rearrangement starting from allylic ester 38 was used in the synthesis of the tocopherol side chain 42 and pine sawfly pheromones (Scheme 5.2.12) [24]. Ireland-Claisen rearrangement of (Z)-allylic ester 38 and in situ reduction of the silyl ester afforded alcohol 39 as a single product Completion... 

The application of fluorous mixture synthesis (FMS) for deriving natural products and their stereoisomers was demonstrated by the total synthesis of all 16 stereoisomers of the pine sawfly sex pheromoned ... 

The sex pheromone of the pine sawfly Diprion pint) is (25,5R, IRYiJ-dimethyltridec-2-yl acetate. This acetate was prepared from diastereomerically enriched (25, 3i , 7i )-3,7-dimethyltridecan-2-ol. 

R, 5R, 75)-3,7-dimethylpentadecan-2-ol, sex pheromone component of the pine sawfly Neodiprion sertifer, has also been synthesized enantioselectively. ... 

Hallberg E. and Lofqvist J. (1981) Morphology and ultrastructure of an intertergal pheromone gland in the abdomen of the pine sawfly Neodiprion sertifer (Insecta, Hymenoptera) a potential source of sex pheromones. Can. J. Zool. 59, 47-53. 

Species of pine sawflies in the genera Neodiprion and Pi prion secrete a sex pheromone dominated by either the acetate or propionate esters of 3,7-dimethylpentadecan-2-ol (138). Reproductive isolation of these sawflies appears to be partly related to the utilization of one or the other of these diasteriomeric esters. 

In the hydrogenation of p keto esters (R, R) tartaric acid gives the (R) alcohols and the (S, S) tartaric acid gives the (S) enantiomers. Raney nickel is more effective than supported nickel catalysts. It appears that the active catalyst is nickel tartrate which is adsorbed on the catalyst surface and that the sodium bromide is adsorbed on the non-chiral active sites, thus, keeping them from promoting the non-selective hydrogenations. 2,84 -pj is procedure has been used to prepare the chiral intermediate in the synthesis of the Pine Sawfly sex pheromone. ... 

Table 11 Pheromone system of pine sawflies. Source Selected data from A. Tai, Yukigosei Kyoukaichi (J. Synthetic Organic Chemistry Japan), 58 576, 2000, and Refs. 47, 48. 

Tai, A., Imaida, M., Oda, T., and Watanabe, H. (1978) Synlliesis of optically active common precursor of sex pheromone of pine sawflies an application of enantioface-differentiating hydrogenation on modified nickel, Chem. Lett. 61-64. 

Reaction of (5)-2-methy1decan-1-y1- 1ithiurn (76) with (3s,4s)-3, 4-dimethyl-Y-butyrolactone (75) has been used to prepare (2s,35,7s)-3,7-dimethylpentadecan-2-ol (77)This alcohol was converted to the acetate and propionate,which are potential pheromones of the European pine sawfly, Neodiprion sertifer. The chiral lactone (75) was obtained from (2S,3S)-trcms-epoxybutane and dimethyl malonate. 

Jewett, D. M., Matsumura, F. and Coppel, H. C. (1976) Sex pheromone specificity in the pine sawflies interchange of acid moieties in an ester. Science, 192, 51-3. 

Kraemer, M., Coppel, H. C., Matsumura, F., Kikukawa, T. and Mori, K. (1979) Field responses of the white pine sawfly. Neodiprion pinetum, to optical isomers of sawfly sex pheromones. Env. Ent., 8, 519-20. 

The same telomer was used by Baker et al. to synthesize the dimethyl-pentadecari 2-ol, the pheromone of the pine sawfly [16]. Also the queen substance, a well-known honey bee pheromone, is formed starting from the malonate telomer, which has exactly the right carbon number and a suitable functionality for a facile synthesis of this natural product (Equation 16) [17]. 

A useful application of the oxy-Cope rearrangement has been used to produce conjugated enynes [e.g. (114) - (115)]. The enyne (115) is an intermediate in a synthesis of the sex pheromone of the Pine Sawfly Neodiprion lecontei. Potassium t-butoxide in liquid ammonia has been found to be the preferred base to produce high yields of the conjugated 1-alkylthio- or l-arylthiobut-3-en-l-ynes (117). Elimination of thiols from the acetylenic disulphides (116) under these conditions completely suppresses the competing formation of cumulene or diene-sulphides. 

The sex pheromone (373) (Scheme 66) of the pine sawfly (Neodiprion lecontei) was synthesized by Kocienski and Ansell (777) as a mixture of epimers starting from 2,6-dimethylcyclohexanone. Alkylation and sub-... 

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