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Graphical abstract Highlights • p -TsOH promoted synthesis of 4-tosyloxy-2 H -chromenes in moderate to excellent yields. • p -TsOH acts not only as a promoter in this reaction, and also as the sulfonate source. • The 4-tosyloxy-2 H -chromenes are versatile intermediates in organic synthesis. • This method can be enlarged to gram scale. Abstract A novel and efficient p -TsOH-promoted cascade cyclization of 2-propynolphenols is developed to give 4-tosyloxy-2 H -chromenes in moderate to efficient yields. It is noted that p -TsOH acts not only as a promoter in this reaction, and also as the sulfonate source. Importantly, the obtained 4-tosyloxy-2 H -chromenes can be used as versatile intermediates for the synthesis of various functionalized compounds through diverse metal-catalyzed cross-coupling reactions. Moreover, this method can be enlarged to gram scale. [ABSTRACT FROM AUTHOR]

• Catalyst- and additive-free synthesis of 2 H -chromen-4-yl phosphinates/phosphonates. • This reaction was achieved by cascade phosphorylation/cyclization of propargylic alcohols and R 2 P(O)OH. • This approach can be enlarged to gram scale. • R 2 P(O)OH acts not only as acid-promoter to initiate the reaction, and also as the phosphinate source. A novel, catalyst- and additive-free cascade phosphorylation/cyclization of readily available 2-propynolphenols with R 2 P(O)OH (R = aryl, OPh, OBn) was developed for the construction of 2 H -chromen-4-yl phosphinates/phosphonates and water as the only byproduct under mild conditions. The reaction was achieved by using R 2 P(O)OH as acid-promoter, but also as the phosphinate source with the formation of phosphorylation allene intermediate, and followed by 6- endo -trig pathway. Additionally, this approach avoided the use of hazardous, air sensitive or activation reagents, and performed well with good functional group tolerance and satisfied yields. [ABSTRACT FROM AUTHOR]

• TFA mediated synthesis of 4-thiocyanated 2 H -chromenes in good to excellent yields. • The 4-thiocyanated 2 H -chromenes are versatile intermediates in organic synthesis. • This approach can be enlarged to gram scale. • This process involves a SCN-containing alleneyl intermediate through S N 1 way. A metal-free, Brønsted acid-mediated cascade cyclization of 2-propynolphenols for efficient synthesis of various 4-thiocyanated 2 H -chromenes is developed by using KSCN as the thiocyanated source. This reaction was characterized by readily prepared starting materials, bearing good functional group tolerance and excellent yields. Moreover, the obtained 4-thiocyanated 2 H -chromenes could be further derivated to potential bioactive and pharmaceutical molecules. [ABSTRACT FROM AUTHOR]