Biocatalysis is one of the most promising technologies for the sustainable synthesis of molecules for pharmaceutical, biotechnological and industrial purposes.

The first enantioselective synthesis was the selective addition of cyanide to benzaldehyde catalysed by a hydroxynitrile lyase (HNL). Since then these enzymes have been developed into a reliable tool in organic synthesis. HNLs to prepare either the (R)- or the (S)-enantiomer of the desired cyanohydrin are available and a wide variety of reaction conditions can be applied. As a result of this, numerous applications of these enzymes in organic synthesis have been described. Here the examples of the last decade are summarised, the enzyme catalysed step is discussed and the follow-up chemistry is shown. This proves HNLs to be part of main stream organic synthesis. Additionally the newest approaches via immobilisation and reaction engineering are introduced.

Enzymes are supreme catalysts when it comes to high enantiopurities and their immobilization will pave the way for continuous operation.

Enantiomerically pure chiral amines are ubiquitous chemical building blocks in bioactive pharmaceutical products and their synthesis from simple starting materials is of great interest. One of the most attractive strategies is the stereoselective installation of a chiral amine through C-H amination, which is a challenging chemical transformation. Herein we report the application of a multienzyme cascade, generated in a single bacterial whole-cell system, which is able to catalyze stereoselective benzylic aminations with ee values of 97.5%. The cascade uses four heterologously expressed recombinant enzymes with cofactors provided by the host cell and isopropyl amine added as the amine donor. The cascade presents the first example of the successful de novo design of a single whole-cell biocatalyst for formal stereoselective C-H amination.

Most theoretical concepts of polymer crystallization have evolved around monolamellar single crystals as model systems. However, such approaches do not account for an important and unique aspect of crystallization of long flexible molecules: the correlated stacking of lamellar crystals. In our experimental work, we focus on the growth kinetics of such stacks of lamellae in thin films of poly­(nonadecane methylphosphonate). Interestingly, concurrent with a decrease in lateral lamellar growth, we observed an increase in vertical growth, that is, an increase in the number of stacked crystalline lamellae. Intriguingly, in contrast to lateral lamellar growth, the rate of such vertical growth increased with decreasing degree of undercooling. Moreover, we show the possibility of forming three-dimensional polymer quasi-single crystals. Some of the formed stacks of lamellar crystals were about 100 times thicker than the initial film; that is, they had a thickness of about 20 times the contour length of the polymer and contained about 800 stacked lamellae. We propose that growth kinetics of stacking of lamellae is governed by (i) the probability of forming self-induced nuclei, (ii) the detachment probability of crystalline stems, and (iii) the influx of molten polymers toward the growth front.

Aliphatic poly(H-phosphonate)s were obtained by polyesterification of dimethyl H-phosphonate with bio-based long-chain diols. Nonadecane-1,19-diol, tricosane-1,23-diol, and octatetracontane-1,48-diol with dimethyl H-phosphonate yield the corresponding polyphosphoesters (PPE19H, PPE23H, and PPE48H) with molecular weights (M n) up to 4.3 × 104 g mol–1. Postfunctionalization of these polymers via Hirao cross-coupling yields the selectively functionalized poly(H-phosphonate)s PPE19Ph, PPE23Ph, and PPE48Ph. DSC analysis revealed significantly enhanced crystallinities and melting points (up to T m = 110 °C) with increasing methylene sequence lengths. Hydrolytic degradation of polymer powder of poly-(H-phosphonate) occurred up to 95% in 2 days. The degradation rates decreased with increasing methylene sequence length. After postfunctionalization, degradation occurred only to a minimal extent over 3 months in basic and in acidic media.

The application of purified enzymes as well as whole-cell biocatalysts in synthetic organic chemistry is becoming more and more popular, and both academia and industry are keen on finding and developing novel enzymes capable of performing otherwise impossible or challenging reactions. The diverse genus Rhodococcus offers a multitude of promising enzymes, which therefore makes it one of the key bacterial hosts in many areas of research. This review focused on the broad utilization potential of the genus Rhodococcus in organic chemistry, thereby particularly highlighting the specific enzyme classes exploited and the reactions they catalyze. Additionally, close attention was paid to the substrate scope that each enzyme class covers. Overall, a comprehensive overview of the applicability of the genus Rhodococcus is provided, which puts this versatile microorganism in the spotlight of further research.

Semicrystalline aliphatic polyphosphoesters can be obtained in a one-step approach by polyesterification of readily available bio-based long-chain diols with dichloro­phosphorus compounds. Nonadecane-1,19-diol and tricosane-1,23-diol with respectively methyl­phosphonic dichloride or phenyl dichlorophosphate yield polymers (PPE19Me, PPE23Me, PPE19­(OPh), and PPE23­(OPh)) with molecular weights M n up to 3 × 104 g mol–1. DSC analysis of these polymers and a C12 analogue reveal significantly enhanced crystallinities and melting points (up to T m = 87 °C) with increasing methylene sequence length. DMA on injection-molded samples shows glass transitions at −19 °C (PPE19Me) and −12 °C (PPE23Me). Single crystals of PPE19Me accommodate a single C19 repeat unit, as concluded from a lamella thickness of only 3 nm thick determined by AFM. Hydrolytic degradation of solid polymer samples under ambient conditions occurred only to a minimal extent over three months by hydrolysis of very small amounts of in-chain anhydride defects.