Naohiro Isono

1,1-1,2-, AND 1,4-ELIMINATIONS FROM THE CORRESPONDING DIHALOGENATED COMPOUNDS USING BU3SNSIME3-F-

Abstract The stannyl anion 2 , generated from Me 3 SiSnBu 3 ( 1 ) 6 in the presence of R 4 NX, CsF or TASF [(Et 2 N) 3 SSiMe 3 F 2 ] 7 in DMF under very mild conditions, 8 was used for 1,1-, 1,2-, or 1,4- elimination of an aryl or vinyl halide with an appropriate leaving group at the α-, β-, or δ-position of halogen. Thus, alkylidene carbene 8 is generated from 1,1-dihalo-alkene 6 or 7 and benzyne 10 is generated from 1,2-dibromobenzene 9 and an o -quinodimethane 12 was produced from α,α′-dibromoxylene 11 a.

Reaction of metal free Bu3Sn− generated from Bu3SnSiMe3-R4NX with an aryl or vinyl halide

Metal free stannyl anion generated from Bu3SnSiMe3 and R4NX in DMF reacted with an aryl or vinyl halide to produce the aryl or vinyl anion via so-called halogen-metal exchange process, which reacted with internal carbonyl group to afford cyclized product in good yield.

Utilization of Me3SiSnBu3 in organic synthesis. Generation of o-quinodimethane from α,α′-dibromo-o-xylene and Me3SiSnBu3-CsF

Abstract The reaction of α,α′-dibromo- o -xylene with stannyl anion generated from Me 3 SiSnBu 3 and CsF or TASF [(Et 2 N) 3 S + SiMe 3 F 2 − ] in the presence of dienophiles afforded the [4+2] cyclization products in good to moderate yields.

Utilization of Me3SiSnBu3 in organic synthesis. I: Generation of a stannyl anion from Me3SiSnBu3 and R4NX

Abstract A metal free stannyl anion generated from Me 3 SiSnBu 3 and R 4NX in DMF reacted with an aryl halide bearing carbonyl group to produce an aryl anion via the so-called halogen-metal exchange process, which reacted with a carbonyl group to afford a cyclized product in good yield.

A NOVEL METHOD OF THREE-CARBON ELONGATION USING BIS(TRIBUTYLSTANNYL)PROPANOL

Abstract The reaction of Me 3 SiSnBu 3 with methyl propiolate in DMF gave methyl 3,3- bistributylstannyl propionate 4 in a high yield The reduction of 4 with LiAlH 4 followed by treatment with MOMCl gave 3,3-bistributylstannyl propanol derivative 7d in aquantitative yield, which was a useful reagent for the C-3 unit elongation. Treatment of 7d with BuLi in THF in the presence of HMPA gave α-stannylated carbanion 10 , which reacted with various electrophiles, such as carbonyl carbons of aldehyde, ketone, and ester, to give C-3 elongation products.