20120-23-4

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The Chematica program was used to autonomously design synthetic pathways to eight structurally diverse targets, including seven commercially valuable bioactive substances and one natural product. All of these computer-planned routes were successfully executed in the laboratory and offer significant yield improvements and cost savings over previous approaches, provide alternatives to patented routes, or produce targets that were not synthesized previously. Although computers have demonstrated the ability to challenge humans in various games of strategy, their use in the automated planning of organic syntheses remains unprecedented. As a result of the impact that such a tool could have on the synthetic community, the past half century has seen numerous attempts to create in silico chemical intelligence. However, there has not been a successful demonstration of a synthetic route designed by machine and then executed in the laboratory. Here, we describe an experiment where the software program Chematica designed syntheses leading to eight commercially valuable and/or medicinally relevant targets; in each case tested, Chematica significantly improved on previous approaches or identified efficient routes to targets for which previous synthetic attempts had failed. These results indicate that now and in the future, chemists can finally benefit from having an “in silico colleague” that constantly learns, never forgets, and will never retire. Multistep synthetic routes to eight structurally diverse and medicinally relevant targets were planned autonomously by the Chematica computer program, which combines expert chemical knowledge with network-search and artificial-intelligence algorithms. All of the proposed syntheses were successfully executed in the laboratory and offer substantial yield improvements and cost savings over previous approaches or provide the first documented route to a given target. These results provide the long-awaited validation of a computer program in practically relevant synthetic design.

A new, highly efficient, inexpensive, recyclable, mild, convenient, and green protocol for chemoselective aza/thia-Michael addition reactions of amines/thiols to α,β-unsaturated compounds using triethylammonium acetate (TEAA) ionic liquid was developed. The catalyst can be recycled ten times and obviate the need for toxic and expensive catalysts.

The 1,4-conjugate addition of primary, secondary and aromatic amines, thiols, and carbamate to α,β-unsaturated compounds mediated by a catalytic amount (0.5 mol%) of RuCl3 in poly(ethylene glycol) (PEG) provides the desired β-substituted carbonyls in high yields. In particular, we found that primary aliphatic and aromatic amines produced the single adducts as the sole products in very high yields with RuCl3-PEG. RuCl 3-PEG was readily recycled via solvent precipitation with efficient recyclability as evidenced by high yields. Its properties of low sensitivity toward moisture and oxygen, high tolerance of different functional groups, and efficient recyclability make RuCl3-PEG suitable for both laboratory and industrial scale synthesis of β-substituted carbonyls. Georg Thieme Verlag Stuttgart.