Fluoroalkanoyl peroxides

The highest yields of 2-perfluoroalkylthiophenes were obtained when bis(per-fluoroalkanoyl)peroxides were used as the source of perfluoroalkyl radicals. Mechanistically reactions with thiophenes (similarly to furans) are considered to be initiated by one-electron transfers from the substrates to peroxide. 

In contrast, it is well known that styrene is a useful radical polymerizable monomer, and diacyl peroxide such as benzoyl peroxide and alkanoyl peroxide are widely used as conventional radical initiators. Since the interaction between theLUMO of diacyl peroxide (e.g., butyryl peroxide) and the HOMO of styrene become extremely weak compared to that of perfluorobutyryl peroxide (see Figure 4.3), the interaction of the SOMO of acyloxy radicals, which produce in the radical decomposition of diacyl peroxides, should interact with the HOMO of styrene to afford the radical polymerization of styrene. In contrast, styrene reacted with fluoroalkanoyl peroxides to afford not the radical polymerizable products but 1 1 adducts [PhCH(OCORp)CH2Rp] via... 

SCHEME 4.2 Synthesis of two fluoroalkyl end-capped acrylic acid oligomer by using fluoroalkanoyl peroxide. 

Alternatively, 5-allyl-2(5/f)-furanones can be obtained from TMSOF and allylic acetates using lithium perchlorate in ether. 5-Propargyl-2(5//)-furanones are prepared by coupling with bex-acarbonyldicobalt complexes of propargylium cations (eq 5). Reaction of the intermediate complex with cerium(TV) ammonium nitrate removes the cobalt Fluoroalkylation is acbieved by using bis(fluoroalkanoyl) peroxides in 1,1,2-tricbloro-1,2,2-trifluoroethane (Freon 113) (eq 6). This process is believed to involve combination of a fluoroalkyl radical with the furan-derived radical cation. 

Co-oligomers of fluorinated silicon containing sulfo groups [135,159] or carboxyl groups [151] have been prepared. Co-oligomerization of fluoroalkanoyl peroxides with acrylic acid and trimethylvinylsilane yielded amphiphilic oligomers soluble and surface active both in water and aromatic solvents, such as benzene, toluene, and w-xylene ... 

Amphiphilic oligomers surface active in both water and aromatic solvents were obtained as well by reacting fluoroalkanoyl peroxides with acrylic acid and dimethylsilcones containing one vinyl or one methacryloxypropyl end group [153]. 

Perfluoropropylated and perfluoro-oxaalkylated 4-vinylpyridinium chloride oligomers have been prepared by reacting fluoroalkanoyl peroxides with 4-vinylpyridinium chloride [216]. 

Fluoroalkylated sulfonic acid oligomers have been prepared by reacting various fluoroalkanoyl peroxides with 2-(methacryloxy) ethanesulfonic acid under mild conditions [218,220] ... 

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