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Covalent organic framework (COF) is a novel platform to develop efficient and green safe heterogeneous photocatalysts. Additionally, multiple photoredox reactions and mechanism studies over porous catalysts remain to be further exploited. In this context, two benzofuran-embedded COFs (BF-COFs) with favorable solvent tolerance were constructed via tautomerism strategy. Attributing to the benzofuran-hetero[6]radialene knots, BF-COFs displayed as donor-acceptor properties, and exhibited wide visible light response range and well separation efficiency for photogenerated charges. Under visible-light, BF-COFs could promote the C-S bond formation reaction between β-ketoate ester and its analogues with NH 4 SCN, affording multi-substituted olefins (28 examples, upto 98% yield) efficiently. Moreover, the atomic economic strategy was also applicative to prepare L -proline derived olefins (≥ 99% ee), which could be further converted into the chiral amino-substituted thiazoles (99% yield and ≥ 99% ee). The research about BF-COFs sheds light on the green construction of C-S bond, (chiral) olefins and chiral amino thiazoles. [Display omitted] • Two benzofuran-heteroradialene joints-embedded BF-COFs were facilely constructed and proved to be donor-acceptor structures. • BF-COFs exhibit remarkable photocatalytic activity for the synthesis of multi-substituted olefins with upto 98% yield (28 examples). • BF-COFs can promote the synthesis of L -proline-derived olefins and amino-substituted thiazoles with maintained chirality (≥ 99% ee). • The photocatalytic mechanism for multi-substituted olefins synthesis were elaborated in detail. [ABSTRACT FROM AUTHOR]