RT info:eu-repo/semantics/article
T1 Polyphosphazenes for the Stille reaction: A new type of recyclable stannyl reagents
A1 Martínez Arranz, Sheila
A1 Presa Soto, David
A1 Carriedo, Gabino A.
A1 Presa Soto, Alejandro
A1 Albéniz Jiménez, Ana Carmen
K1 Polyphosphazenes
AB The random phosphazene copolymer {[N=P((CH2)7-Br)Ph]0,5[N=PMePh]0,5}n (2) and the block copolyphosphazene {[N=P((CH2)7-Br)Ph]25[N=PMePh]20}-b-[N=P(O2C12H8)]55 (5), having a branch with two randomly distributed units, have been synthesized and used as precursors for the stannyl derivatives {[N=P((CH2)7-SnBu2An)Ph]0,5[N=PMePh]0,5}n (3) and{[N=P((CH2)7-SnBu2An)Ph]25[N=PMePh]20}-b-[N=P(O2C12H8)]55 (6, An = p-MeOC6H4). Polymers 3 and 6 were tested as recyclable tin reagents in the Stille cross-coupling reaction with C6H5I, using various Pd catalysts and different experimental conditions. Polymer 6 can be recycled without significant release of tin, but its efficiency decreased after three consecutive cycles. This effect was explained by studying the self-assembly of the polymer under the same conditions used for the catalytic experiments, which evidenced the progressive coalescence of the polymeric vesicles (polymersomes) leading to stable and bigger core-shell aggregates by the attraction of the [N=P(O2C12H8)] rich membranes, thus decreasing the accessibility of the tin active centers.
PB Royal Society of Chemistry
SN 1477-9226
YR 2016
FD 2016
LK http://uvadoc.uva.es/handle/10324/21781
UL http://uvadoc.uva.es/handle/10324/21781
LA eng
NO Dalton Transactions, 2016,45, p.. 2227-2236
NO Producción Científica
DS UVaDOC
RD 19-abr-2024