Synthesis of Vicinal Dichlorides via Activation of Aliphatic Terminal Epoxides with Triphosgene and Pyridine

Highly sensitive and selective detection of triphosgene with a 2-(2'-hydroxyphenyl)benzimidazole derived fluorescent probe

In this work, a 2-(2'-hydroxyphenyl)benzimidazole derived fluorescent probe, 2-(2'-hydroxy-4'-aminophenyl)benzimidazole (4-AHBI), was synthesized and its fluorescent behavior toward triphosgene were evaluated. The results showed that 4-AHBI exhibited high sensitivity (limit of detection, 0.08 nM) and excellent selectivity for triphosgene over other acyl chlorides including phosgene in CH2Cl2 solution. Moreover, 4-AHBI loaded test strips were prepared for the practical sensing of triphosgene.

A decade review of triphosgene and its applications in organic reactions

This review article highlights selected advances in triphosgene-enabled organic synthetic reactions that were reported in the decade of 2010-2019. Triphosgene is a versatile reagent in organic synthesis. It serves as a convenient substitute for the toxic phosgene gas. Despite its first known preparation in the late 19th interestingly began only three decades ago. Despite the relatively short history, triphosgene has been proven to be very useful in facilitating the preparation of a vast scope of value-added compounds, such as organohalides, acid chlorides, isocyanates, carbonyl addition adducts, heterocycles, among others. Furthermore, applications of triphosgene in complex molecules synthesis, polymer synthesis, and other techniques, such as flow chemistry and solid phase synthesis, have also emerged in the literature.

Triphosgene and DMAP as Mild Reagents for Chemoselective Dehydration of Tertiary Alcohols

The utility of triphosgene and DMAP as mild reagents for chemoselective dehydration of tertiary alcohols is reported. Performed in dichloromethane at room temperature, this reaction is readily tolerated by a broad scope of substrates, yielding alkenes preferentially with the (E)-geometry. While formation of the Hofmann products is generally favored, a dramatic change in alkene selectivity toward the Zaitzev products is observed when the reaction is carried out in dichloroethane at reflux.

Total synthesis of pyrano[3,2-e]indole alkaloid fontanesine B by a double cyclization strategy

The regioselective synthesis of pyrano[3,2-e]indole alkaloid fontanesine B by two different cyclizations is described. The complete regioselectivity is controlled by the C4 Pictet–Spengler cyclization, in which an iminium ion acts as a transient directing (TDG) group. Furthermore, carbolines were constructed by a new Bischler–Napieralski-type cyclization, in which an unprecedented trichloromethyl carbamate serves as a reactive group.

The regioselective synthesis of pyrano[3,2-e]indole alkaloid fontanesine B have been accomplished by C4 Pictet–Spengler cyclization and Bischler–Napieralski-type cyclization of a trichloromethyl carbamate.