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1,1-雙金屬化合物與芳香基硫縮醛在鎳觸媒的催化下可進行烯化反應。在這個反應中，
1,1-雙金屬化合物是偕位碳雙陰離子的合成組元，而硫縮醛可被視為偕位碳雙陽離子的合
成組元。
格林納試劑與炔丙基硫縮醛的在鎳觸媒的催化下進行偶合反應生成丙二烯。這是
第一個同時引進1,3-取代基在丙二烯上的合成方法，適用於三取代及四取
代丙二烯的合成。
在這個反應中，炔丙基硫縮醛是1,3-丙二烯雙碳陽離子的合成組元。
有機銅陰離子試劑與炔丙基硫縮酮反應，接著以不同的親電試劑焠熄，得到位置選擇的
親電基取代丙二烯硫醚或炔丙基硫醚。在這個反應中，有機銅陰離子試劑不進行常見的1,
4-加成反應，反而攻擊炔丙基硫縮酮上的硫原子生成丙二烯銅及炔丙基銅這兩個反應中間
體。利用這個反應，在炔丙基硫縮酮g-位置引入一個離去基，可以進一步合成[3]-聯烯。
而將丙二烯銅及炔丙基銅這兩個反應中間體與溴化鋅進行金屬轉換反應，產生丙二烯鋅及
炔丙基鋅反應中間體，則可在鈀觸媒催化下與sp2的親電試劑進行偶合反應，生成sp2親電
基取代丙二烯硫醚。在相同的反應條件下以甲基碘為親電試劑時，產物得到脫硫二聚化的
烯雙炔。
有機鈦金屬試劑與炔丙基硫縮酮進行脫硫二聚化反應生成烯雙炔。分子內雙炔丙基硫縮
酮與鈦金屬試劑亦可反應得到環化的烯雙炔。
Ni-catalyzed coupling reactions of 1,1-bismetallic reagent and aromatic
dithioacetals give the corresponding olefination products. In these reactions,
the 1,1-bismetallic reagent acts as a geminal dianion synthon and the
dithioacetal can be treated as a geminal dication synthon.
Ni-catalyzed coupling reactions of a propargylic dithioacetals with Grignard
reagents give allenes as only products. This is the first
example of introducing
1,3-substituents in allene synthesis in one pot which can be considered as a
general reaction for the synthesis of tri- and tetra-substituted allenes. In
this regard, the propargylic dithioacetals serves as a 1,3-allene dication
synthon.
Treatment of propargylic dithioketals with organocuprate reagents followed by
quenching with different electrophiles affords regioselectively substituted
allenyl thioethers or propargylic thioethers. The organocuprate
reagent, instead
of undergoing a Michael type addition, attacks sulfur atom to generate allenyl
copper and/or propargylic copper as intermediate. Propargylic dithioketals
heaving a g-leaving group reacts with organocuprate reagent to afford the
corresponding [3]-cumulenes. Transmetallation of allenyl copper and/or
propargylic copper with ZnBr2 followed by Pd-catalyzed coupling reaction with
sp2 electrophilic reagents to give the corresponding substituted allenyl
thioethers. When MeI is used as an electrophile dimeric endiynes are obtained.
Reactions of propargylic dithioketals with organotitaninm reagent again yield
endiynes. The reaction can also occur intramolecularly.
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