The use of polymer supports in organic synthesis. VIII. Solid phase syntheses of insect sex attractants

Abstract

7 were oxidized with the Sharpless reagent (CrO,Cl,/tert-butyl alcohol/pyridine) to give polymer-bound aldehydes [35][36][37], which on reaction with Wittig reagents and subsequent hydrolysis and acetylation gave 28, 29, and 10-tetradecen-1-01 acetate (47)

The use of polymer supports in organic synthesis. XII. The total stereoselective synthesis of cis insect sex attractants on solid phases

“…Mesylation of 5 and 6 in benzene-pyridine (3: 1) gave the polymer-bound symmetrical diol monomesylates 7 and 8 respectively. The amounts of diols bound to 5 and 6 and the yields of monomesylates derived from 7 and 8 were determined by acid cleavage as previously described (2) and are recorded in Table 1.…”

“…On a effectuC des essais pour rCduire d'une f a~o n stCrCosClective les alcynes internes liks au polymkre afin d'obtenir des alcknes cis; a cette fin on a fait appel au 9-borabicyclononane, a I'hydrure de diisobutylaluminium et au catkchol-borane mais tous ces rtactifs s'avkrent inadCquats a cause soit d'une rCduction incomplkte, d'une rCduction trop grande, d'une hydrogCnolyse de l'alcyne du polymkre ou a cause de la non-sClectivitC. On a pu rkduire quantitativement les alcynes internes liCs au polymtre et obtenir exclusivement les attractants sexuels des insectes cis en faisant appel au disiamylborane sans obtenir de rkduction supplCmentaire ou d'hydrogtnolyse.[Traduit par le journal] 'Holder of NRCC Studentships 1974-1977 …”

“…Une scission acide de 9 et 10 conduit respectivement aux dCcyn-9 01-1 et dodCcyn-11 01-1. Une nouvelle Ctape de couplage, effectute par la lithiation Introduction Recently, we have reported the preparation of insect sex attractants (shown below) of Lepidopcis where m = 1-3 and n = 6,8-10 tera on solid phases by an alkyne coupling route and by two different Wittig sequences (1,2). The yields of reactions on solid phases, the use of symmetrical starting materials (3), the simplicity of solid phase reactions (4,5), and the potential for synthesis in an automated procedure (6) showed distinct promise over solution phase methods, but several problems remained to be solved for the complete stereoselective synthesis of insect sex attractants (7) on solid phases.…”

“…Furthermore, in our previous syntheses on solid phases via the alkyne coupling route, the polymer-bound alkyne was cleaved from the polymer before stereoselective reduction to cis insect sex attractants was attempted. The stereoselective reduction was then achieved using 9-borabicyclononane (9-BBN) in solution (2,8). A complete solid phase synthesis of cis insect sex attractants would require that the stereoselective cis reduction of an internal alkyne be accomplished directly on the polymer support.…”

The solid phase synthesis of monoester monoamides and monoester monoalcohols from symmetrical diacid chlorides

“…Thus, the loading capacities of poly~ner 5 for 1--4 were determined by isolation of their respective diesters 14-17 and are recorded in Table 1. Treatment of the polymer-bound acid chlorides (6-9) with aniline (18) and 9 with benzylamine (19), dimethylamine (20), and a~nmonia (21), respectively, gave the polymer-bound nionoester monoamides 22-28, respectively. The ir spectra of 22-28 all exhibited intense absorptions at 1740 cnl-' and between 1650-1700 cm-' indicative of the ester and aniide functional groups, respectively.…”