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An efficient and catalyst-free synthesis of trisubstituted allylic sulfones through an allylic sulfonylation reaction of Morita-Baylis-Hillman (MBH) carbonates with sodium sulfinates has been developed. Under the optimized reaction conditions, a series of trisubstituted allylic sulfones were rapidly prepared in good to excellent yields (71%-99%) with good to high selectivity (Z/E from 79:21 to >99:1). Compared with known synthetic methods, the current protocol features mild reaction temperature, high efficiency and easily available reagents.

A variety of biologically and synthetically useful 3-alkenyloxindoles were rapidly synthesised via an SN2′-type allylic substitution reaction of isatin-derived Morita–Baylis–Hillman carbonates with sodium sulfinates. The syntheses were conducted under catalyst-free reaction conditions and good to excellent product yields (up to 96%) and Z/E selectivities (up to >20:1) were obtained.

A Lewis base mediated three-component, one-pot allylic substitution reaction of Morita-Baylis-Hillman (MBH) carbonates with water and 1-phenyl-5-methylsulfonyltetrazole (PTSO2Me) has been developed. In the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO), a series of 1-phenyl-5-functionalized tetrazoles are prepared in moderate to excellent yield (40-97%). The key reaction mechanism is rationalized by the ipso-substitution of PTSO2Me with hydroxide which derives from deprotonation of water.Morita-Baylis-Hillman (MBH) adducts or their derivatives are valuable synthetic intermediates since they provide versatile functionalities for further synthetic transformations. 1 Recently, the allylic substitution reactions of MBH acetates or carbonates as electrophiles, through a SN2'-SN2' cascade, by metal-free catalysis of nucleophilic tertiary amines or phosphines have emerged as a very powerful strategy for the construction of densely functionalized compounds in a rapid and atom-economic way and under mild reaction conditions. 2 Since the pioneering work conducted by Lu and co-workers, 3 the high synthetic potential of MBH carbonates has been actively investigated with recognition of the much superior reactivity of tert-butoxycarbonyl (Boc) group, and thus allowing the application of a variety of nucleophiles. 4 In 2002, Kim and co-workers reported the use of cinchona alkaloid derivatives for the hydrolysis of MBH acetate with sodium bicarbonate as a water surrogate. 5 This reaction followed the

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