C-N bond formation reactions are of great importance in organic chemistry, containing the synthesis of pharmaceutical/agrochemical reagents, dyes, natural products, polymers and other fine chemicals (Scheme 1). Past decades witnessed the repaid development of synthesis for various organic amines, including catalytic reduction of nitriles and nitro compounds, reductive amination of aldehydes and ketones with ammonia hydroamination of alkynes and reduction of amides. Despite
these achievements, it is still highly desirable to develop other methods for the formation of C-N bonds. The direct C-N bond formation of amines with alkylated reagents has been extensively studied. The outstanding transformations have been achieved by the reactions such as aryl halides with amines, hydroaminations and hydroaminomethylation. Besides, the coupling reaction of amines with alcohol via borrowing-hydrogen methodology is one of the most promising strategies to construct N-alkylated amines because alcohols are readily available, inexpensive, and nontoxic. Barta, Hu, Balaraman, Wendt,  Chung,  Peng, Gupta, Türkmen, and Shi reported the N-alkylation of amines with alcohols. Compared with long-chain aliphatic and aromatic alcohols,  the coupling reactions of amines and methanol are more difficult for the borrowing-hydrogen process, although methanol as a methylating reagent attracts more attention than others, such as methyl iodide, formaldehyde, formic acid, acetic acid, carbon dioxide, dimethylcarbonate. Diverse catalytic samples have shown that the dehydrogenation of methanol is the initial and rate-determining step in N-methylation reactions. The reason is that compared with other higher alcohols, methanol has higher activation energy in the dehydrogenation process. Thus, the methylation of amines with methanol still remains challenging. Herein, we aim to show a complete review of the reported catalytic examples for the catalytic direct coupling reaction of
amines with methanol, providing a helpful understanding of the  relationship between catalyst structure and catalytic performance. To make it easy for the reader, this article is organized according to kinds of catalytic systems including homogenous, heterogenous and  photocatalytic catalysts for both N-methylation and N,N-dimethylation reactions. Finally, we will afford the indications for future progress in this field.