{'fraction_non_alphanumeric': 0.03160270880361174, 'fraction_numerical': 0.020316027088036117, 'mean_word_length': 5.253521126760563, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
A phosphine-mediated construction of 1,4-oxazepines and 1,3-oxazines.

A simple and efficient method for constructing 1,4-oxazepines and 1,3-oxazines was developed with use of a phosphine-mediated tandem reaction of ynones with 2-azido alcohols. The method offers a promising route to synthetically useful as well as biologically active heterocycles under mild conditions and may be exploited for the preparation of interesting chiral ligands.